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The Web Development Glossary
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    • The Web Development Glossary
    • Acknowledgments
    • About the Glossary
    • !important
    • .gitignore
    • .htaccess
    • .htpasswd
    • .NET
    • .NET Framework
    • /dev/null
    • __qem
    • 8.3
    • 11ty
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    • 992
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    • A
    • A List Apart
    • A/B testing
    • A11Y
    • AAA
    • AAAA
    • Above the fold
    • Absolute domain name
    • Abstract Data Type
    • Abstraction
    • Accelerated Mobile Pages
    • Accept-CH
    • Acceptance Test-Driven Development
    • Acceptance testing
    • Access control
    • Access Control List
    • Access Keys
    • Access logs
    • Access token
    • Accessibility
    • Accessibility Conformance Testing
    • Accessibility Object Model
    • Accessibility tree
    • Accessible Rich Internet Applications
    • ACID
    • Acid tests
    • ACK
    • ACL
    • ACM
    • Acq-hiring
    • Acqui-hiring
    • ACSS
    • ACT
    • Action item
    • ActionScript
    • Active Server Pages
    • Active Users
    • ActiveX
    • Adaptive
    • Adaptive loading
    • Adaptive technology
    • Addon
    • Address Resolution Protocol
    • Adobe ColdFusion
    • Adobe Dreamweaver
    • Adobe Flash
    • Adobe Photoshop
    • ads.txt
    • ADT
    • Advanced Encryption Standard
    • Advanced Package Tool
    • Advanced Persistent Threat
    • AES
    • Advanced Persistent Threat
    • AES
    • Affordance
    • Agile
    • Agile Manifesto
    • AirMosaic
    • AJAX/Ajax
    • ALA
    • ALGOL
    • Algorithm
    • Algorithmic Language
    • Aliasing
    • Almost standards mode
    • Almost strict mode
    • Alternate style sheet
    • Amaya
    • Amazon Resource Name
    • Amazon Route 53
    • Amazon S3
    • Amazon Silk
    • Amazon Simple Queue Service
    • Amazon Simple Storage Service
    • Amazon SQS
    • Amazon Virtual Private Cloud
    • Amazon VPC
    • Amazon Web Services
    • AMD
    • American National Standards Institute
    • American Standard Code for Information Interchange
    • AMP
    • Analytics
    • Anchor
    • Angular
    • AngularJS
    • Animation
    • Anonymous block box
    • Anonymous block element
    • Anonymous function
    • Anonymous inline box
    • Anonymous inline element
    • Anonymous text
    • ANSI
    • Anti-pattern
    • AOM
    • AOMedia Video 1
    • Apache
    • Apache HTTP Server
    • Apache Maven
    • Apache Subversion
    • Apache Tomcat
    • Apache Weex
    • API
    • API gateway
    • App
    • App shell
    • Apple Safari
    • Apple Universal Access
    • Applet
    • Application
    • Application Context
    • Application Programming Interface
    • Application-Layer Protocol Negotiation
    • APT
    • → Advanced Persistent Tool
    • AR
    • Arena
    • Argument
    • ARIA
    • ARIA roles
    • ARN
    • ARP
    • Arrange, Act, Assert
    • Array
    • Arrow function
    • ASCII
    • ASI
    • ASP
    • ASP.NET
    • Aspect ratio
    • AssemblyScript
    • Assignment
    • Assistive technology
    • Assistive Technology Service Provider Interface
    • Association for Computing Machinery
    • Asynchronous
    • Asynchronous Module Definition
    • Asynchronous JavaScript and XML
    • at
    • AT
    • at-rule
    • AT-SPI
    • ATAG
    • ATDD
    • Atlassian Bitbucket
    • Atlassian Jira
    • Atom
    • Atomic CSS
    • Atomicity, Consistency, Isolation, Durability
    • Attribute
    • Attribute minimization
    • Augmented Reality
    • Authentication
    • Authoring tool
    • Authoring Tool Accessibility Guidelines
    • Authorization
    • Automagic
    • Automatic Semicolon Insertion
    • Automation
    • Autonomous custom element
    • AV1
    • AV1 Image File Format
    • Availability Zone
    • AVIF
    • AWS
    • AZ
    • BA
    • Babel
    • Back/forward cache
    • Backend
    • Backend for Frontend
    • Backlink
    • Backup
    • Backup redundancy
    • Backward compatibility
    • Bad Neighborhood
    • Bada
    • Bandwidth
    • Banner
    • Barrierefreie-Informationstechnik-Verordnung
    • Base64
    • Baseline
    • Bash
    • Basic access authentication
    • Basic Multilingual Plane
    • BDD
    • Behavior
    • Behavior-Driven Development
    • Below the fold
    • BEM
    • Best practice
    • Bézier curve
    • Bfcache
    • BFF
    • BGP
    • BHO
    • Bidirectional
    • Bidi
    • Bidirectional
    • Big Bang
    • Big integer
    • Big O notation
    • Binary chop
    • Binary large object
    • Binary number
    • Binary search algorithm
    • Binding
    • Bitbucket
    • Bitmap
    • BITV
    • Black hat
    • Black Mode
    • Black-box testing
    • Blacklist
    • Blink
    • Blisk
    • Blob
    • Block
    • Block box
    • Block container
    • Block container box
    • Block container element
    • Block element
    • Block Element Modifier
    • Block flow
    • Block formatting context
    • Block-level box
    • Block-level element
    • Blog
    • Blogging
    • Blogosphere
    • BMP
    • BOM
    • Bookmark
    • Bookmark icon
    • Bookmarklet
    • Boolean
    • Bootstrap
    • Border
    • Border Gateway Protocol
    • Bottom posting
    • Bounce rate
    • Bound variable
    • Boundary value problem
    • Bounding box
    • Bourne shell
    • Bower
    • Box
    • Box model
    • Box model hack
    • Boyscout Rule
    • Bracket notation
    • Braille (⠃⠗⠁⠊⠇⠇⠑)
    • Branch
    • Branch predication
    • Branching
    • BREAD
    • Breadcrumb
    • Breakpoint
    • Brewer’s Theorem
    • Bring Your Own License
    • Broken link
    • Brotli
    • Browse, Read, Edit, Add, Delete
    • Browser
    • Browser detection
    • Browser engine
    • Browser extension
    • Browser Helper Object
    • Browser sniffing
    • Browser testing
    • Browser War
    • Browsing
    • Browsing context
    • Buffer
    • Bug
    • Bug tracking system
    • Bugfix
    • Bugzilla
    • Build Verification Test
    • Bundling
    • BVT
    • BYOL
    • Byte Order Mark
    • Bytecode
    • CA
    • Cache
    • Cache busting
    • Cache eviction
    • Cache partitioning
    • Cache poisoning
    • California Consumer Privacy Act
    • Call stack
    • Call to Action
    • Callback
    • Callback queue
    • Camel case
    • Camino
    • Canary
    • Candidate Recommendation
    • Canonical equivalence
    • Canonical link
    • Canonical Name
    • Canvas
    • CAP Theorem
    • CAPTCHA
    • Card sorting
    • Caret
    • Carousel
    • Cascade
    • Cascading HTML Style Sheets
    • Cascading Style Sheets
    • Case
    • catch
    • CBD
    • CBSE
    • CC/PP
    • CCPA
    • CCT
    • ccTLD
    • CD
    • CDATA
    • CDN
    • CDP
    • CERT
    • Certificate
    • Certificate Authority
    • CES
    • CFML
    • CGI
    • Chaining
    • Change list
    • Change set
    • Changeset
    • Channel messaging
    • Chaos engineering
    • Character
    • Character Data
    • Character encoding
    • Character entity reference
    • Character reference
    • Character set
    • Charset
    • CheiRank
    • Chrome
    • Chrome Custom Tabs
    • Chrome DevTools
    • Chrome DevTools Protocol
    • Chrome OS
    • ChromeVox
    • Chromium
    • CHSS
    • CI
    • CIDR
    • Cipher
    • CircleCI
    • CL
    • Class
    • Class variable
    • Classitis
    • Classless Inter-Domain Routing
    • Clearfix
    • CLI
    • Click
    • Click-through rate
    • Clickjacking
    • Client
    • Client Hints
    • Client side
    • Client-Side Rendering
    • Cloaking
    • Clojure
    • Clone detection
    • Closure
    • Cloud
    • Cloud computing
    • Cloud storage
    • CLS
    • Cluster
    • CMP
    • CMS
    • CMYK
    • CNAME
    • CNAME cloaking
    • Coalescing
    • CoC
    • Code
    • Code coverage
    • Code debt
    • Code golf
    • Code of Conduct
    • Code point
    • Code refactoring
    • Code review
    • Code smell
    • Code splitting
    • Codeline
    • CodePen
    • Coding by Convention
    • Coding guidelines
    • COEP
    • CoffeeScript
    • Cognitive disability
    • Cold data
    • ColdFusion
    • ColdFusion Markup Language
    • Collapsed margin
    • Color blindness
    • Color circle
    • Color management
    • Color scheme
    • Color wheel
    • Comma-Separated Values
    • Command
    • Command-Line Interface
    • Command-Query Separation
    • Comment
    • Common Gateway Interface
    • Common Vulnerabilities and Exposures
    • Common Vulnerability Scoring System
    • CommonJS
    • CommonMark
    • Community of Practice
    • Compared to what?
    • Compass
    • Compatibility
    • Compatibility equivalence
    • Compatibility mode
    • Compiler
    • Compiling
    • Complementary colors
    • Component
    • Component library
    • Component-Based Development
    • Component-Based Software Engineering
    • Composite Capability/Preference Profiles
    • Compression
    • Computer programming
    • Concurrent Versioning System
    • Concurrent Versions System
    • Conditional
    • Conditional Comments
    • Cone of Uncertainty
    • Confidence testing
    • Confidentiality Agreement
    • Conflict of interest
    • Connection draining
    • Consent Management Platform
    • Console
    • Constant
    • Constructor
    • Container
    • Containerization
    • Containing block
    • Content
    • Content box
    • Content category
    • Content Delivery Network
    • Content Management System
    • Content network
    • Content optimization
    • Content Security Policy
    • Context switch
    • Continuous Delivery
    • Continuous Deployment
    • Continuous Integration
    • Continuous Media
    • Contrast
    • Control flow
    • Convention over Configuration
    • Conversion
    • Conway’s Law
    • Cookie
    • Cookie banner
    • Cookie consent
    • Cookie hijacking
    • CoP
    • CORB
    • Core Web Vitals
    • CORP
    • Corporate Design
    • Corporate Identity
    • CORS
    • Cost-per-click
    • Country code top-level domain
    • Coupling
    • CPA
    • CPC
    • CPM
    • CQS
    • CR
    • Craft
    • CRAP
    • Crawler
    • Crawling
    • Create, Read, Update, Delete
    • Create, Replicate, Append, Process
    • Critical CSS
    • Critical path
    • Critical path analysis
    • Critical path method
    • Critical rendering path
    • CRM
    • cron
    • Cron job
    • Crontab
    • Cross-Origin Read Blocking
    • Cross-Origin Resource Sharing
    • Cross-Origin Resource Policy
    • Cross-Origin-Embedder-Policy
    • Cross-Site Request Forgery
    • Cross-Site Script Inclusion
    • Cross-Site Scripting
    • Cross-Site WebSocket Hijacking
    • CRP
    • CRUD
    • CSCS
    • CSP
    • CSR
    • CSRF
    • CSS
    • CSS framework
    • CSS lock
    • CSS Modules
    • CSS Object Model
    • CSS preprocessor
    • CSS Zen Garden
    • CSS-in-JS
    • CSS-Tricks
    • CSSOM
    • CSV
    • CSWSH
    • CTA
    • CTR
    • Cumulative Layout Shift
    • curl
    • Currying
    • Custom data attribute
    • Custom element
    • Custom property
    • Custom Effort Score
    • Customer Relationship Management
    • Customized built-in element
    • Customized Scripting in C#
    • Cutting the mustard
    • CVE
    • CVS
    • CVSS
    • Cyan, Magenta, Yellow, and Key
    • Cycle time
    • Cyclomatic complexity
    • D3.js
    • DAD
    • Daemon
    • Daily Active Users
    • Daily Scrum
    • DAM
    • Dark Mode
    • Dark pattern
    • Darknet
    • Dart
    • Data
    • Data center
    • Data Control Language
    • Data Definition Language
    • Data lake
    • Data Manipulation Language
    • Data Query Language
    • Data storage
    • Data Stream Management System
    • Data swamp
    • Data type
    • Data visualization
    • Data warehouse
    • data- * attribute
    • Database
    • Database engine
    • Database index
    • Database language
    • Database Management System
    • Database server
    • DAU
    • DAVE
    • DBC
    • DBMS
    • DCE
    • DCL
    • DCVS
    • DDA
    • DDD
    • DDL
    • DDoS
    • Dead code elimination
    • Dead letter queue
    • Debugging
    • Declaration
    • Declaration block
    • Decoration
    • Decryption
    • Deep linking
    • Deep Web
    • Defect
    • Defect tracking system
    • Definition of “Done”
    • Delete, Add, View, Edit
    • Demilitarized Zone
    • Denial of Service
    • Deno
    • Dependency
    • Dependency injection
    • Dependency Inversion Principle
    • Deployment
    • Deployment environment
    • Deprecated
    • Deprecation
    • Descender
    • Deserialization
    • Design
    • Design by Contract
    • Design language
    • Design system
    • Design strategy
    • Design vocabulary
    • Destructuring
    • Developer Experience
    • Developer tools
    • Development and operations
    • Development Team
    • DevEx
    • Device orientation
    • Device pixel
    • DevOps
    • DevTools
    • DHCP
    • DHTML
    • Dialog box
    • Digital Asset Management
    • Digital Rights Management
    • DIP
    • Directionality
    • Disability Discrimination Act
    • Disciplined Agile Delivery
    • Display advertising
    • Display resolution
    • Distributed Concurrent Versions System
    • Distributed Persistent Rendering
    • Distributed Version Control System
    • Dither
    • Divitis
    • Django
    • DKIM
    • DLR
    • DMARC
    • DML
    • DMZ
    • DNAME
    • DNS
    • DNS over HTTPS
    • DNS root zone
    • DNS spoofing
    • DNSKEY
    • DNSSEC
    • → Domain Name System Security Extensions
    • DocBook
    • Docker
    • DOCTYPE
    • Document directive
    • Document Object Model
    • Document Style Semantics and Specification Language
    • Document type declaration
    • Document Type Definition
    • Documentation
    • DoH
    • Dojo
    • DOM
    • DOM clobbering
    • Domain
    • Domain expert
    • Domain name
    • Domain name server
    • Domain Name Service
    • Domain Name System
    • Domain Name System Security Extensions
    • Domain sharding
    • Domain-Based Message Authentication, Reporting, and Conformance
    • Domain-Driven Design
    • DomainKeys Identified Mail
    • Don’t Repeat Yourself
    • Doorway page
    • DoS
    • Dot file
    • Dot notation
    • Dot-agnostic
    • Dots per inch
    • Double
    • Downstream
    • Downtime
    • Downward compatibility
    • DPI
    • DPR
    • DQL
    • Dreamweaver
    • Driver
    • DRM
    • DRY
    • DSMS
    • DSSSL
    • DTD
    • Duck typing
    • Dup
    • Duplicate code
    • DVCS
    • DW
    • DWH
    • DX
    • Dynamic
    • Dynamic Host Configuration Protocol
    • Dynamic HTML
    • Dynamic Language Runtime
    • Dynamic password
    • Dynamic Scope
    • Dynamic typing
    • Dyslexia
    • E-commerce
    • E2E
    • EAA
    • EAT
    • EBCDIC
    • EBM
    • Eclipse
    • ECMA
    • Ecma International
    • ECMAScript
    • ECT
    • Edge
    • Edge caching
    • Editor
    • EditorConfig
    • EFF
    • Effective Connection Type
    • Effectiveness
    • Efficiency
    • EIP
    • Elastic IP
    • Elasticity
    • Electron
    • Electronic Frontier Foundation
    • Element
    • Eleventy
    • else
    • Em
    • Emacs
    • Email
    • Email address
    • Email spoofing
    • Embedded content
    • Embedded style sheet
    • EME
    • Empiricism
    • Empty element
    • Empty string
    • Encapsulation
    • Encrypted Media Extensions
    • Encryption
    • End of file
    • End of line
    • End tag
    • End-to-end testing
    • Entity
    • Entity graph
    • Entity identifier
    • Entity reference
    • Environment variable
    • EOF
    • EOL
    • Ephemeral storage
    • Epic
    • Equal-width typeface
    • Equality Act 2010
    • Error
    • ES
    • ES Modules
    • ES4
    • ES6
    • Ethics
    • ETL
    • Etiquette
    • European Accessibility Act
    • European Computer Manufacturers Association
    • Event
    • Event handler
    • Event loop
    • Event-driven architecture
    • Eventual consistency
    • Evidence-Based Management
    • Exception
    • Exception handling
    • Exception handling syntax
    • Exit code
    • Exit status
    • Expertise, Authoritativeness, Trustworthiness
    • Express
    • Extended Binary Coded Decimal Interchange Code
    • Extensible Application Markup Language
    • Extensible HyperText Markup Language
    • Extensible Markup Language
    • Extensible Stylesheet Language
    • Extensible Stylesheet Language Transformations
    • External
    • Extract, Transform, Load
    • Extreme Programming
    • Eye tracking
    • FaaS
    • Facade pattern
    • Fagan inspection
    • Fagan testing
    • Failover
    • Fallback
    • False negative
    • False positive
    • Falsy
    • Fat footer
    • Favelet
    • Favicon
    • Favorite
    • FCP
    • Feature creep
    • Feature detection
    • Feature phone
    • Feature testing
    • Federal Information Processing Standard
    • Federated Learning of Cohorts
    • Federation
    • Feed
    • Feed reader
    • Fetch API
    • FID
    • FIFO
    • Figma
    • File
    • File locking
    • File manager
    • File system
    • File Transfer Protocol
    • Fingerprinting
    • FIPS
    • Firebird
    • Firefox
    • First Contentful Paint
    • First CPU Idle
    • First In, First Out
    • First Input Delay
    • First Interactive
    • First Meaningful Paint
    • First Paint
    • First Public Working Draft
    • First-class function
    • First-order function
    • Fitts’s Law
    • Fixed
    • Flash
    • Flash of Faux Text
    • Flash of Invisible Text
    • Flash of Unstyled Content
    • Flash of Unstyled Text
    • Flash Player
    • Flat Design
    • Flex
    • Flexbox
    • Float
    • FLoC
    • Flock
    • FLOSS
    • Flow content
    • Flow of control
    • Fluent Design System
    • Fluid
    • FMP
    • FOAF
    • FOFT
    • Fold
    • FOIT
    • Folksonomy
    • Font
    • Font Awesome
    • Font block period
    • Font failure period
    • Font subsetting
    • Font swap period
    • Foobar
    • for
    • foreach
    • Foreign key
    • Fork
    • Form
    • Formatting context
    • Formatting Output Specification Instance
    • Forward compatibility
    • Forward proxy
    • Forward secrecy
    • FOSI
    • FOSS
    • FOUC
    • FOUT
    • FPS
    • FPWD
    • FQDN
    • Fragment identifier
    • Frame
    • Frame busting
    • Frame rate
    • Framekiller
    • Frames per second
    • Framework
    • Frameset
    • Free and Open Source Software
    • Free Software Foundation
    • Free variable
    • Friend of a Friend
    • Frontend
    • FrontPage
    • fs
    • FS
    • FSF
    • FTP
    • FTP over SSH
    • FTP Secure
    • FTP-SSL
    • FTP
    • Fugu
    • Full Service
    • Full Stack
    • Full stack developer
    • Fully qualified domain name
    • Function
    • Function as a Service
    • Function binding
    • function*
    • Functional programming
    • Functional testing
    • FutureSplash
    • Fuzz testing
    • Fuzzing
    • Gamma
    • Garbage collection
    • Garbage In, Garbage Out
    • Gateway
    • Gatsby
    • GCP
    • GDPR
    • Gecko
    • General Data Protection Regulation
    • General Image Manipulation Program
    • General Responsibility Assignment Software Patterns
    • Generator
    • Generator function
    • Generic top-level domain
    • Geofence
    • Geolocation API
    • Geturl
    • GIF
    • GIGO
    • GIMP
    • Git
    • GitHub
    • GitHub Copilot
    • GitLab
    • Global
    • Global object
    • Global scope
    • Global variable
    • Globally unique identifier
    • Glyph
    • GNU
    • GNU General Public License
    • GNU Project
    • Go
    • Goanna
    • Golang
    • Golden mean
    • Golden ratio
    • Golden section
    • Google Chrome
    • Google Cloud Platform
    • Google Lighthouse
    • Google QUIC
    • Google TalkBack
    • Google Web Server
    • Gopher
    • GPL
    • GPU
    • gQUIC
    • Graceful Degradation
    • Grapheme
    • Graphic
    • Graphical User Interface
    • Graphics Interchange Format
    • Graphics Processing Unit
    • GraphQL
    • GRASP
    • Greasemonkey
    • Greeking
    • Greenfield project
    • Grid
    • Grid computing
    • Grid track
    • gTLD
    • Guetzli
    • gulp
    • gulp.js
    • Gutter
    • GUI
    • GUID
    • GWS
    • gzip
    • Hackathon
    • Hacker
    • Haml/HAML
    • Handlebars
    • Hard reset
    • Hash
    • Hash function
    • Hash table
    • Hash-Based Message Authentication Code
    • Hashbang
    • Hashtag
    • hasLayout
    • HCI
    • HDD
    • Head-of-line blocking
    • Heading content
    • Headless
    • Health check
    • HEIC
    • HEIF
    • Helper class
    • Heterogenous migration
    • Hex
    • Hex triplet
    • Hexadecimal
    • Hick’s Law
    • Hick-Hyman Law
    • Hidden Web
    • High Efficiency Image Coding
    • High Efficiency Image File Format
    • Higher-order component
    • Higher-order function
    • HIP
    • Hit
    • HITS
    • HMAC
    • HMAC-Based One-Time Password
    • HOC
    • Hoisting
    • HOL blocking
    • Holey
    • Home page
    • Home Page Reader
    • Home screen
    • Homepage
    • HomeSite
    • Homogenous migration
    • Hooking
    • Hop limit
    • Horizontal scaling
    • Host
    • Host Identity Protocol
    • Hostname
    • Hot data
    • Hot linking
    • HOTP
    • Hotwire
    • Houdini
    • HPR
    • HSL
    • HSTS
    • HSV
    • HTML
    • HTML Abstraction Markup Language
    • HTML over the wire
    • HTML template
    • HTML 5
    • HTML/CSS framework
    • HTML5
    • HTML5 Boilerplate
    • HTTP
    • HTTP flood attack
    • HTTP method
    • HTTP request method
    • HTTP status code
    • → 0-9 for various HTTP status codes
    • HTTP Strict Transport Security
    • HTTP verb
    • HTTP/2
    • HTTP/3
    • httpd.conf
    • HTTPS
    • HTTPS Everywhere
    • HubDB
    • HubL
    • HubSpot Markup Language
    • Hue, Saturation, Lightness
    • Hue, Saturation, Value
    • Hugo
    • Human-Computer Interaction
    • humans.txt
    • Hungarian notation
    • Hydration
    • Hype cycle
    • Hyperlink
    • Hyperlink-Induced Topic Search
    • Hypertext
    • HyperText Markup Language
    • Hypertext Preprocessor
    • Hypertext Transfer Protocol
    • Hypertext Transfer Protocol Secure
    • Hypervisor
    • Hypothesis-Driven Development
    • I/O
    • I18N
    • IA
    • IaaS
    • IAB
    • IaC
    • IANA
    • IBM Home Page Reader
    • IBM WebExplorer
    • ICANN
    • Icon
    • Icon font
    • ID
    • ID selector
    • IDE
    • Identifier
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    • if
    • Iframe
    • IIFE
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    • Image
    • Image map
    • Image replacement
    • IMAP
    • Immediately Invoked Function Expression
    • Immutable
    • In-App Browser
    • Inclusive Design
    • Increment
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    • Indexed color
    • Indexed Database
    • IndexedDB
    • Indexing
    • IndieWeb
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    • Infinite loop
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    • Information architecture
    • Information Design
    • Information foraging
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    • Information scent
    • Information Security
    • Information Security Operations Center
    • Infosec
    • Infrastructure as a Service
    • Infrastructure as Code
    • Inheritance
    • Initiative for Open Authentication
    • Inline
    • Inline box
    • Inline element
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    • Inline linking
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    • Inline-level box
    • Inline-level element
    • innerHTML
    • Input/Output
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    • Insertion mode
    • Instance store
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    • Instant Articles
    • Institute of Electrical and Electronics Engineers
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    • Interaction Design
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    • Interface
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    • Interface Segregation Principle
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    • Internal
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    • Internet
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    • Internet Explorer
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    • InterNIC
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    • Interpolation
    • Intersection Observer
    • Interstitial
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    • Inversion of Control
    • Inverted Triangle CSS
    • IoC
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    • iOS
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    • IP address
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    • IPFS
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    • iptables
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    • JAWS
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    • Joomla
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    • jQuery
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    • JSON
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    • JSON Web Signature
    • JSON Web Token
    • JSON with Padding
    • JSON-LD
    • JSON-P
    • JSON5
    • JSON5 Data Interchange Format
    • JSP
    • JSS
    • JSSS
    • JSX
    • Just in Time
    • Just-in-time compilation
    • JVM
    • JWS
    • JWT
    • K-Meleon
    • K8s
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    • Kerberos
    • Kerning
    • Key
    • KEY
    • Key frame
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    • Key Performance Indicator
    • Key-value database
    • Keyframe
    • Keyword
    • KHTML
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    • Konqueror
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    • L10N
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    • LAMP
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    • Language
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    • Last In, First Out
    • Latency
    • LaTeX
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    • Law of Conservation of Complexity
    • Layout
    • Layout engine
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    • Lazy loading
    • LCP
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    • LDAP
    • Lead time
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    • Lean
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    • Legibility
    • Less/LESS
    • LeSS
    • Let’s Encrypt
    • Letter spacing
    • Lexical scope
    • Library
    • Library World Wide Web
    • libwww
    • LIFO
    • Ligature
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    • Lighthouse
    • Lightweight Directory Access Protocol
    • Likert scale
    • Line box
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    • Linear Responsibility Chart
    • Lines of Code
    • Link
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    • Link farm
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    • Linked Data
    • Linter
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    • Linux
    • Linux Standard Base
    • Linux, Apache, MySQL, PHP/Perl/Python
    • Liquid
    • LIS
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    • Lisp/LISP
    • Lit
    • Lite Mode
    • LitElement
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    • Little’s Law
    • LML
    • Load balancer
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    • Load balancing
    • Load time
    • LOC
    • Local
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    • Local variable
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    • Localization
    • Location information server
    • Lock file
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    • Long task
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    • longdesc
    • Look and feel
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    • LRC
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    • LTR
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    • Lynx
    • MAC
    • MAC address
    • Mac OS
    • Machine Learning
    • macOS
    • macOS, Apache, MySQL, PHP/Perl/Python
    • Macromedia Flash
    • MacWWW
    • Magic code
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    • Mail
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    • Maintainability
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    • Makefile
    • MAM
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    • Man-in-the-middle attack
    • Manifesto for Agile Software Development
    • Margin
    • Margin collapsing
    • Markdown
    • Marketing
    • Markup
    • Markup language
    • Massively Parallele Processing
    • Masthead
    • Material Design
    • Mathematical markup language
    • Mathematical Markup Language
    • MathML
    • MAU
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    • MD
    • MD2
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    • MD5
    • MD6
    • MDL
    • MDN
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    • MDX
    • MEAN
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    • Media query
    • Media type
    • Medium integer
    • Mega menu
    • Memoization
    • Menu
    • Merge request
    • Merging
    • Message Authentication Code
    • Message Digest
    • Meta-element
    • Metadata
    • Metadata content
    • Method
    • Method stub
    • Metro
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    • Microformat
    • Microservice
    • Microservice architecture
    • Microsite
    • Microsoft Active Accessibility
    • Microsoft Design Language
    • Microsoft Edge
    • Microsoft FrontPage
    • Microsoft Silverlight
    • Microsoft Windows
    • Microtask
    • Middleware
    • Millenium bug
    • MIME
    • MIME sniffing
    • MIME type
    • Mini Program
    • Minification
    • Minifier
    • Minimum Viable Product
    • MIP
    • MITM
    • Mixin
    • ML
    • Mobile
    • Mobile First
    • Mobile Instant Pages
    • Mobilegeddon
    • Mocha
    • Modal
    • Model-View-Controller
    • Model-View-Viewmodel
    • Modernizr
    • Modular design
    • Module
    • Monolith
    • Monolithic application
    • Monorepo
    • Monthly Active Users
    • Mosaic
    • Moving Picture Experts Group
    • Mozilla Developer Center
    • Mozilla Developer Network
    • Mozilla Firefox
    • MPEG
    • MPP
    • MR
    • MSA
    • MSAA
    • MSHTML
    • MSIE
    • mTLS
    • Multi-factor authentication
    • Multimedia
    • Multiple inheritance
    • Multipurpose Internet Mail Extensions
    • Muphry’s Law
    • Murphy’s Law
    • Mustache
    • Mutable
    • Mutation
    • Mutual authentication
    • Mutual TLS authentication
    • MVC
    • MVP
    • MVVM
    • MX
    • MySQL
    • n-based indexing
    • NACK
    • NACL
    • NAK
    • Name binding
    • Name server
    • Namespace
    • NaN
    • NAT
    • National Institute of Standards and Technology
    • Native
    • NativeScript
    • Natural interface
    • Natural key
    • Natural user interface
    • Navigation
    • Navigator
    • NDA
    • Negative space
    • Nesting
    • Net Promoter Score
    • Netscape 4
    • Netscape Communicator
    • Netscape Navigator
    • Network
    • Network Information Center
    • Network Mapper
    • Network packet
    • Neutral character
    • Newbie
    • Newline
    • News aggregator
    • Next.js
    • Nexus
    • NGINX
    • Night Mode
    • Ninety-Ninety Rule
    • NIST
    • Nmap
    • Node
    • Node Package Manager
    • Node.js
    • nofollow
    • Nolan’s Law
    • Non-Disclosure Agreement
    • Non-relational database
    • Nonce
    • NonVisual Desktop Access
    • Noob
    • Normal form
    • Normalization
    • Normalize.css
    • Normative
    • NoSQL
    • Not a Number
    • npm
    • NPS
    • NS
    • NUI
    • Null
    • Null device
    • Null pointer
    • Number
    • Number sign
    • Numeral
    • Numeric character reference
    • Numeric up/down
    • Numerical digit
    • Nuxt.js
    • NVDA
    • OATH
    • OAuth
    • Obfuscation
    • Object
    • Object-Oriented CSS
    • Object-Oriented Programming
    • Objectives and Key Results
    • Observer
    • Observer pattern
    • OCP
    • OCSP
    • OCSP stapling
    • Offline
    • Offline First
    • OGP
    • OIDC
    • OKR
    • OLAP
    • OLTP
    • One-based indexing
    • One-Time Password
    • Online Analytical Processing
    • Online Certificate Status Protocol
    • OOCSS
    • OOM
    • OOP
    • OOPIF
    • Open Authorization
    • Open Graph Protocol
    • Open Source
    • Open Systems Interconnection model
    • Open Web Application Security Project
    • Open-Closed Principle
    • OpenID
    • OpenID Connect
    • OpenType
    • Opera
    • Opera Mini
    • Operand
    • Operating System
    • Operator
    • Optimization
    • Optional markup
    • Orca
    • Origin
    • Origin trials
    • Orphan
    • Orthogonality
    • OS
    • OSI model
    • OTA
    • OTF
    • OTP
    • Out of memory
    • Out-of-process Iframe
    • Outline
    • Over the Air
    • OWASP
    • PaaS
    • package.json
    • package-lock.json
    • Packaged Offline/Online Webpage
    • Packed
    • Packet
    • Padding
    • Page
    • Page impression
    • Page parking
    • Page prediction
    • Page Quality
    • Page view
    • PageRank
    • PageSpeed
    • Paint
    • Pair programming
    • Palpable content
    • Paper prototyping
    • Paradigm
    • Parallax scrolling
    • Parallel browsing
    • Parameter
    • Paraphrase testing
    • Parcel
    • Pareto Principle
    • Parkinson’s Law
    • Parased Character Data
    • Parser
    • Parsing
    • Pascal case
    • Patch
    • Path
    • PATH
    • Pattern
    • Pattern library
    • Pave the cowpaths
    • Pay-per-click
    • Payload
    • Paywall
    • PBI
    • PCDATA
    • PDF
    • Peer review
    • Pen test
    • Penetration testing
    • Perceivable, Operable, Understandable, and Robust
    • Perceived performance
    • Percent encoding
    • Performance
    • Performance budget
    • Performance indicator
    • Perl
    • Permalink
    • Persona
    • Personal data
    • Personal Home Page
    • Personally identifiable information
    • PhantomJS
    • Phishing
    • Phoenix
    • Photoshop
    • PHP
    • PhpStorm
    • Phrasing content
    • PII
    • Pinball pattern
    • Ping
    • Pinging
    • pip
    • Pixel
    • Pixel tag
    • Pixel-perfect
    • Placeholder
    • Placeholder text
    • Plain-text
    • Plane
    • Platform as a Service
    • Platform modernization
    • Playback attack
    • Plugin
    • PNG
    • Pointer
    • Pointing device
    • Polyfill
    • Polymer Project
    • POM
    • POP
    • Pop-under
    • Pop-up
    • Port
    • Port number
    • Portable code
    • Portable Document Format
    • Portable Network Graphics
    • Portal
    • Post mortem
    • Post Office Protocol
    • PostCSS
    • Postel’s Law
    • POUR
    • POW
    • PowerShell
    • PPC
    • PQ
    • PR
    • Pre-production environment
    • Preact
    • Predication
    • Prefetching
    • Preferred style sheet
    • Premature optimization
    • Prerendering
    • Presentation
    • Presto
    • Primary key
    • Primitive
    • Principal box
    • Print style sheet
    • Privacy
    • Product Backlog
    • Product Backlog Item
    • Product Owner
    • Production
    • Production environment
    • Programming
    • Programming language
    • Progressive Enhancement
    • Progressive font enrichment
    • Progressive rendering
    • Progressive Web App
    • Project Object Model
    • Promise
    • Prop
    • Property
    • Protocol
    • Prototype
    • Prototyping
    • Proxy
    • Proxy Server
    • PRPL
    • Pseudo-class
    • Pseudo-code
    • Pseudo-element
    • PTR
    • Pull request
    • Punycode
    • Puppet
    • Puppeteer
    • Push notification
    • Push technology
    • PV
    • PWA
    • Python
    • QA
    • QC
    • qooxdoo
    • QPS
    • Quality
    • Quality Assistance
    • Quality Assurance
    • Quality Control
    • Quantity query
    • Queries per second
    • Query
    • Query language
    • QUIC
    • Quick UDP Internet Connections
    • Quirks mode
    • Race condition
    • Race hazard
    • RACI matrix
    • RADIUS
    • Rails
    • Raku
    • RAM
    • Random variable
    • Random-Access Memory
    • Ranking
    • Raster image
    • Rate limiting
    • Rax
    • RCDATA
    • RCS
    • RDBMS
    • RDF
    • RDF Site Summary
    • RDP
    • RDSMS
    • React
    • React Native
    • Reactive Extensions for JavaScript
    • Reactive Manifesto
    • Reactive programming
    • ReactJS
    • Read the Fucking Manual
    • Read-Eval-Print Loop
    • Readability
    • Reading disorder
    • README
    • Real User Monitoring
    • RealAudio
    • Really Simple Syndication
    • RealVideo
    • Recidivism
    • Recommendation
    • Recovery Point Objective
    • Recovery Time Objective
    • Recursion
    • Red, Green, and Blue
    • Redesign
    • Redirect
    • Redirect chain
    • Redundancy
    • Redux
    • Reed-Solomon codes
    • Refactoring
    • Reference error
    • Referential opacity
    • Referential transparency
    • Reflow
    • Regex
    • Registrar
    • Regular expression
    • Rehydration
    • Relational Data Stream Management System
    • Relational database
    • Relational Database Management System
    • Relational model
    • Relative sizing
    • Relaunch
    • Rem
    • Remote Authentication Dial-In User Service
    • Remote Desktop Protocol
    • Remote method invocation
    • Render tree
    • Renderer
    • Rendering
    • Rendering engine
    • RenderingNG
    • REP
    • REPL
    • Replaceable Character Data
    • Replaced element
    • Replay attack
    • Repo
    • Repository
    • Representational State Transfer
    • Request
    • Request for Comments
    • Request header
    • Request method
    • Requests per second
    • RequireJS
    • Reset
    • Reset style sheet
    • Resolution
    • Resource Description Framework
    • Resource Hints
    • Resource record
    • Response
    • Response header
    • Responsibility Assignment Matrix
    • Responsive design
    • Responsive Images Community Group
    • Responsive web design
    • Responsiveness
    • REST
    • Restricted production
    • Revalidation
    • Reverse proxy
    • Revision control
    • Revision Control System
    • RFC
    • RGB
    • RIA
    • RIB
    • RICG
    • Rich Internet Application
    • Rich Site Summary
    • Rich Text Format
    • Rich Web Application
    • Right-to-left
    • Rijndael
    • RIRO
    • RMI
    • Roadmap
    • Robot
    • Robots Exclusion Protocol
    • Robots exclusion standard
    • robots.txt
    • Robustness Principle
    • Root
    • Root directory
    • Root element
    • Root em
    • Root name server
    • Root node
    • Root server
    • Root zone
    • Rooting
    • Round-Trip Delay Time
    • Round-Trip Time
    • Route 53
    • Router
    • Routine
    • Routing
    • Routing Information Base
    • Routing table
    • RPC
    • RPM
    • RPM Package Manager
    • RPO
    • RPS
    • RR
    • RSS
    • RTD
    • RTF
    • RTFM
    • RTL
    • RTO
    • RTT
    • Rubber ducking
    • Rubbish In, Rubbish Out
    • Ruby
    • Ruby on Rails
    • Rule
    • Rule set
    • RUM
    • Runbook
    • Runtime compilation
    • RWD
    • RxJS
    • S3
    • SaaS
    • Safari
    • SAFe
    • SAK
    • Samba
    • Same origin
    • Same-origin policy
    • SAML
    • SAN
    • Sandbox
    • SAP User Interface for HTML5
    • SAPUI5
    • Sass
    • SassScript
    • SAST
    • Scalable and Modular Architecture for CSS
    • Scalable Vector Graphics
    • Scalar
    • Scaled Agile Framework
    • Scaled Scrum
    • Schema stitching
    • SCM
    • Scope
    • Scoped styles
    • Screen magnifier
    • Screen reader
    • Script
    • Scripting language
    • Scroll Snap
    • Scrolling
    • Scrollport
    • Scrum
    • Scrum Master
    • Scrums of Scrums
    • Scrum Team
    • Scrum Values
    • SCSS
    • SDK
    • SDLC
    • SDP
    • SEA
    • SeaMonkey
    • Search Engine Advertising
    • Search engine indexing
    • Search Engine Marketing
    • Search Engine Optimization
    • Search Engine Results Page
    • Searching
    • Section 508
    • Sectioning content
    • Secure context
    • Secure Shell
    • Secure Sockets Layer
    • Security
    • Security Assertion Markup Language
    • Security hacker
    • Security Operations Center
    • security.txt
    • Selector
    • Selenium
    • SEM
    • Semantic Versioning
    • Semantic Web
    • Semantics
    • SemVer
    • Sender Policy Framework
    • SEO
    • Separation of Concerns
    • Serialization
    • Serif
    • SERP
    • Server
    • Server cluster
    • Server farm
    • Server logs
    • Server Name Indication
    • Server push
    • Server side
    • Server-Side Rendering
    • Serverless computing
    • Service discovery
    • Service discovery protocol
    • Service Level Agreement
    • Service Level Expectation
    • Service worker
    • Service-oriented architecture
    • Servlet
    • Session
    • Session affinity
    • Session hijacking
    • Session storage
    • Set
    • SFTP
    • SGML
    • Shadow DOM
    • Shadow host
    • Shadow root
    • Shadow tree
    • Shared hosting
    • Shared tenancy
    • Shared worker
    • Shebang
    • Shell
    • Shim
    • Shockwave Flash
    • Shortcut icon
    • Shorthand
    • SI
    • Siamese twins document
    • SIG
    • Sign-in
    • Sign-on
    • Signed HTTP Exchanges
    • Silk
    • Silverlight
    • Simple Mail Transfer Protocol
    • Simple Object Access Protocol
    • Single point of failure
    • Single Responsibility Principle
    • Single-Page Application
    • Site
    • Site isolation
    • Site map
    • Sitemaps
    • Skeleton screen
    • Sketch
    • Skin
    • Skip navigation
    • SLA
    • SLE
    • Sliding Doors
    • SLOC
    • Sloppy mode
    • Slot
    • Slowloris
    • Slug
    • SMACSS
    • Small integer
    • Smashing Magazine
    • SME
    • Smi
    • SMIL
    • Smishing
    • Smoke testing
    • SMTP
    • Snake case
    • Snap position
    • SNI
    • Snowpack
    • SOA
    • SOAP
    • SOC
    • Social Web
    • Soft launch
    • Soft opening
    • Software
    • Software as a Service
    • Software crisis
    • Software development
    • Software Development Kit
    • Software Development Life Cycle
    • Software framework
    • Software modernization
    • Software stack
    • Software testing
    • SOLID
    • Solution stack
    • SOP
    • Source Code Management
    • Source Control Management
    • Source Lines of Code
    • SPA
    • Spacer
    • Spaghetti code
    • Spam
    • Spamdexing
    • Spamming
    • SPDY
    • Spec
    • Specification
    • Specificity
    • Spectre
    • Speech synthesis
    • Speed Index
    • SPF
    • Spider
    • Spike
    • Spinner
    • Splash screen
    • SPOF
    • Spoofing
    • Spread
    • Sprint
    • Sprint Goal
    • Sprite
    • SQL
    • SQL injection
    • SQS
    • Squad
    • Squarespace
    • src
    • sRGB
    • SRI
    • SRP
    • SRV
    • SSG
    • SSH
    • SSH File Transfer Protocol
    • SSIM
    • SSL
    • SSR
    • Stack
    • Stack level
    • Stack Overflow
    • Stacking context
    • Staging
    • Staging environment
    • Stand-up
    • Standard
    • Standard Generalized Markup Language
    • standard Red Green Blue
    • Standards mode
    • Standby redundancy
    • Star
    • Star hack
    • Start of Authority
    • Start page
    • Start tag
    • State
    • Statement
    • Static
    • Static Application Security Testing
    • Static scope
    • Static Site Generation
    • Static Site Generator
    • Status code
    • Sticky session
    • Stimulus
    • Storage
    • Storage area network
    • Storage engine
    • Storybook
    • Strada
    • Stream
    • Streaming media
    • Strict mode
    • String
    • Strong character
    • Structural Similarity Index Measure
    • Structure
    • Structured Query Language
    • Stub
    • Style guide
    • Style sheet
    • Styled component
    • styled-components
    • stylelint
    • Styling
    • Stylus
    • Subject Alternative Name
    • Subject-Matter Expert
    • Subnav
    • Subnavigation
    • Subnet
    • Subnet mask
    • Subnetwork
    • Subresource Integrity
    • Subroutine
    • Subsetting
    • Subversion
    • SUIT CSS
    • Superkey
    • Superuser
    • Support
    • Surface Web
    • Surfing
    • Surrogate key
    • SVG
    • SVN
    • Switchover
    • SXG
    • Symbol
    • Symfony
    • SYN
    • Synchronized Multimedia Integration Language
    • Synchronous
    • Syndication
    • Syntactic sugar
    • Syntax
    • Syntax analysis
    • syslog
    • Tab
    • Tab icon
    • Tabbed Document Interface
    • Table box
    • Table formatting context
    • Tabnabbing
    • Tabular data
    • Tachyons
    • Tag
    • Tag Management System
    • Tag soup
    • Tagging
    • Tailoring
    • TalkBack
    • tar
    • Tarball
    • TBT
    • Tcl
    • TCP
    • TDD
    • TDI
    • TDZ
    • Tech Lead
    • Tech Twitter
    • Technical and organizational measure
    • Technical key
    • Technical debt
    • Technical Lead
    • Technical Program Manager
    • Technical standard
    • Technological Protection Measures
    • Telnet
    • Template
    • Template language
    • Template processor
    • Template system
    • Temporal Dead Zone
    • Temporary storage
    • Ten-Second Rule
    • Terminal
    • Ternary operator
    • Tesler’s Law
    • Test pyramid
    • Test-Driven Development
    • Testing
    • TeX
    • Text-to-speech
    • Textile
    • The Onion Router
    • The Open Group Architecture Framework
    • Theme
    • Third party
    • this
    • Thread
    • Three-Click Rule
    • TIL
    • Time box
    • Time to First Byte
    • Time to Interactive
    • Time to Live
    • Time-Based One-Time Password
    • Timed text
    • Timestamp
    • tink
    • Tiny integer
    • Tizen
    • TL
    • TLD
    • TLS
    • TLS Certificate Status Request extension
    • TMS
    • To-do
    • Toast
    • Todo
    • TOFU
    • TOGAF
    • Token
    • Tokenization
    • TOM
    • Tom’s Obvious, Minimal Language
    • Tomcat
    • TOML
    • Tooling
    • Top-level domain
    • Top posting
    • TOP500
    • Tor
    • Tor Browser
    • Tor network
    • Tor Project
    • Total Blocking Time
    • TOTP
    • TPM
    • Tracer code
    • Tracing
    • Tracking
    • Tracking pixel
    • Trade
    • Transclusion
    • Transcompiler
    • Transcreation
    • Transcript
    • Transmission Control Protocol
    • Transpiler
    • Transport Layer Security
    • Travis CI
    • Tree-shaking
    • Triadic colors
    • Trident
    • TrueType
    • Trust on First Use
    • Trust Upon First Use
    • Trusted Types
    • TrustRank
    • try
    • try … catch
    • TTF
    • TTFB
    • TTI
    • TTS
    • TTL
    • TUFU
    • Turbo
    • Turbo mode
    • Turbo pages
    • Turing completeness
    • Two-factor authentication
    • TXT
    • Type
    • Type coercion
    • Type conversion
    • Type design
    • Type I error
    • Type II error
    • Type system
    • Typeface
    • TypeScript
    • TYPO3
    • Typography
    • UA
    • UA string
    • UAAG
    • UAT
    • UCD
    • UDD
    • UDJO
    • UDP
    • UDP flood attack
    • Uglification
    • UI
    • UI framework
    • UI redressing
    • UIML
    • UMD
    • UML
    • undefined
    • Underscore hack
    • Unicode
    • Unicode Consortium
    • Unicode Standard
    • Unified Modeling Language
    • Uniform Resource Characteristic
    • Uniform Resource Identifier
    • Uniform Resource Locator
    • Uniform Resource Name
    • Uninitialized pointer
    • Uninitialized variable
    • Unique Selling Point
    • Unique Selling Proposition
    • Unique Value Proposition
    • Unit testing
    • Universal Access
    • Universal Cross-Site Scripting
    • Universal Design
    • Universal Module Definition
    • Universal selector
    • Universally unique identifier
    • Universal XSS
    • Uniwidth typeface
    • Unix/UNIX
    • Unix philosophy
    • UPA
    • Upstream
    • URC
    • Urchin Tracking Module
    • URI
    • URL
    • URL encoding
    • URL forwarding
    • URL redirection
    • URL slug
    • URN
    • Usability
    • Usability inspection
    • Usability Professionals Association
    • Usability testing
    • Usenet
    • User
    • User acceptance testing
    • User agent
    • User Agent Accessibility Guidelines
    • User agent sniffing
    • User agent string
    • User Datagram Protocol
    • User Experience
    • User Experience Professionals Association
    • User Interface
    • User interface markup language
    • User JavaScript
    • User story
    • User testing
    • User-Centered Design
    • User-Driven Development
    • Userscript
    • Using Declarations Just Once
    • USP
    • UTF-8
    • UTF-16
    • UTF-32
    • Utility class
    • UTM
    • UUID
    • UVP
    • UX
    • UXPA
    • UXSS
    • Validation
    • Validator
    • Value
    • Value-Driven Design
    • Variable
    • Variable font
    • Variable scope
    • VBA
    • VDD
    • Vector image
    • Velocity
    • Vendor prefix
    • Verification
    • Version control
    • Versioning
    • Vertical scaling
    • vi
    • Viewport
    • Vim
    • Virtual inheritance
    • Virtual LAN
    • Virtual Machine
    • Virtual Machine Manager
    • Virtual Machine Monitor
    • Virtual Private Cloud
    • Virtual Private Network
    • Virtual Reality
    • Virtualization
    • Virtualizer
    • Visual Basic for Applications
    • Visual formatting model
    • Visual impairment
    • Visual regression testing
    • Visual Studio Code
    • Vishing
    • VLAN
    • VM
    • VMM
    • Voice over IP
    • Voice phishing
    • VoiceOver
    • VoiceXML
    • Void element
    • VoIP
    • VPC
    • VPN
    • VR
    • VRT
    • VS Code
    • Vue
    • Vue.js
    • VuePress
    • Vuex
    • W3C
    • WAF
    • WAI
    • WAI-ARIA
    • WAMP
    • WAN
    • WAP
    • WAR
    • Wasm
    • WaSP
    • Waterfall
    • WAU
    • WCAG
    • WCAG Samurai
    • Weak character
    • Web 2.0
    • Web Accessibility Initiative
    • Web address
    • Web analytics
    • Web app
    • Web application
    • Web application archive
    • Web Application Firewall
    • Web Application Framework
    • Web beacon
    • Web browser
    • Web bug
    • Web Bundles
    • Web cache
    • Web component
    • Web content
    • Web Content Accessibility Guidelines
    • Web design
    • Web development
    • Web Distributed Authoring and Versioning
    • Web feed
    • Web font
    • Web forms
    • Web framework
    • Web Graphics Library
    • Web Hypertext Application Technology Working Group
    • Web IDL
    • Web indexing
    • Web Open Font Format
    • Web Packaging
    • Web page
    • Web performance
    • Web Performance Optimization
    • Web platform
    • Web Platform Incubator Community Group
    • Web resource
    • Web service
    • Web site
    • Web standard
    • Web standards movement
    • Web Standards Project
    • Web storage
    • Web tracking
    • Web typography
    • Web Video Text Tracks
    • Web Vitals
    • Web worker
    • WebAssembly
    • WebAuthn
    • WebDAV
    • WebExplorer
    • WebGL
    • WebKit
    • Webkrauts
    • Weblog
    • WebM
    • Webmaster
    • Webmention
    • WebP
    • webpack
    • WebPageTest
    • Website
    • WebSocket
    • WebStorm
    • WebView
    • WebVTT
    • WeChat Mini Program
    • Weebly
    • Weekly Active Users
    • Weex
    • WeiXin Markup Language
    • WeiXin Script
    • WeiXin Style Sheets
    • Well-formedness
    • WET
    • Wget
    • What You See Is All You Get
    • What You See Is What You Get
    • WHATWG
    • while
    • White-box testing
    • Whitelist
    • Whitespace
    • WHOIS
    • WICG
    • Wide area network
    • Widow
    • Wiki
    • Window-Eyes
    • Windows
    • Windows Aero
    • Windows, Apache, MySQL, PHP/Perl/Python
    • WIP
    • Wireframe
    • Wireless Application Protocol
    • Wireless Markup Language
    • Wix
    • WML
    • Wobbly Transformation Format 8-Bit
    • WOFF
    • WORA
    • WordPress
    • WordPress Theme
    • Work in Progress
    • Workaround
    • Workbox
    • Working Draft
    • Worklet
    • World Wide Web
    • World Wide Web Consortium
    • WorldWideWeb
    • WPO
    • Wrapper
    • Write Once, Run Anywhere
    • WTF-8
    • WWW
    • WXML
    • WXS
    • WXSs
    • WYSIAYG
    • WYSIWYG
    • X.509
    • x-height
    • XAML
    • XForms
    • XHP
    • XHR
    • XHTML
    • XLink
    • XML
    • XML Schema Definition
    • XML User Interface Language
    • XML-RPC
    • XMLHttpRequest
    • XP
    • XPath
    • XPointer
    • XQuery
    • XSD
    • XSL
    • XSLT
    • XSRF
    • XSS
    • XSSI
    • XUL
    • Y2K
    • YAGNI
    • Yahoo Developer Network
    • Yahoo Query Language
    • Yahoo User Interface
    • Yahoo User Interface Library
    • YAML
    • YAML Ain’t Markup Language
    • Yandex Browser
    • Yarn
    • yarn.lock
    • YDN
    • Year 2000 problem
    • Yet Another Multicolumn Layout
    • yield
    • YMYL
    • You Aren’t Gonna Need It
    • Your Money or Your Life
    • YSlow
    • YUI
    • Z shell
    • Zero-based indexing
    • Zero-configuration networking
    • Zero-indexed
    • Zeroconf
    • ZIP
    • Zombie cookie
    • Zone file
    • Zsh
    • Wikipedia Contributions
    • MDN Web Docs Contributions
    • About The Web Development Glossary

Introduction

This is a glossary for web development.

It covers more than 2,000 [with the latest update more than 3,000] important, useful, and historic terms and abbreviations relevant for web (and software) developers.

The glossary acquaints and reunites you with the major standards and concepts of the Web, with HTML, CSS, JavaScript, accessibility, security, performance, code quality, internationalization, localization, editors and tooling and more. It then goes beyond web development, touching computer science, design, typography, usability and user experience, information as well as project management, other disciplines of interest and relevance to the modern developer. It goes beyond, encouraging to stay curious to learn more about the Web and the people creating and using it.

The glossary does not tell in the same way as other books do, but it still tells a story. It tells a story that is sterile yet messy. It tells a story that only started three decades ago and that is still unfolding. It tells a story that starts with you. Why you? Because you are at your own stage of web development—and because web development is only unfolding, only so alive, because of people like you, people who take a personal interest in it. When you read the glossary like you would read another book, you may noticed. (Yet still, it is a glossary.)

About the Glossary

Many explanations and definitions in this glossary are based on Wikipedia and the MDN Web Docs. It was neither necessary nor desirable to come up with a new and different explanation for every term.

Arrows (“→”) point to the expanded forms of abbreviations, and to the more common synonyms and expressions. Sometimes they take you on a little detour, but only to be transparent about the journey taken (like Personal Home Page → PHP → Hypertext Preprocessor, or HTML5 → HTML → HyperText Markup Language). This may seem lengthy, but it aims to make meanings, relationships, and sometimes history more clear. An arrow may also point at a term that encompasses the referring term, or at a related concept, and therefore does not necessarily indicate identity or equivalence.

Whenever there is a source of great quality or immediate use, explanations include references to external documentation and software.

Some terms and abbreviations have several meanings. Only the tech-related ones are shown.

Sometimes there is imprecision: Is a home page a special type of web page, but a homepage another word for a website? (Per this book, trying to gauge how “most” people use the respective terms, this is so.)

Unfortunately, there are going to be inconsistencies, probably errors, and perhaps also controversy. Please help improve the glossary as well as, if applicable, Wikipedia and MDN Web Docs. Giving back to the communities, work on the book has led to numerous small improvements to both Wikipedia and MDN Web Docs articles, but it is unlikely that these improvements covered all there was to improve. Thank you for sharing your knowledge and taking the time to contribute as well.

This all being said: Enjoy. Web Development is a great field.

Licenses

The Web Development Glossary is licensed under a CC BY-SA 4.0 (Attribution-ShareAlike 4.0 International) license.

Material from Wikipedia is licensed under a CC BY-SA 3.0 license.

Material from MDN Web Docs is licensed under a CC BY-SA 2.5 license.

Material from the HTML Living Standard is licensed under a CC BY 4.0 license.

A great number of explanations build on Wikipedia. They are marked “†” and likewise attributed in the Appendix. The original material is licensed under a CC BY-SA 3.0 license.

Some explanations build on the MDN Web Docs. They are marked “‡” and likewise attributed in the Appendix. The original material is licensed under a CC BY-SA 2.5 license.

A handful of explanations build on the HTML Living Standard. They are marked “§”. The original material is licensed under a CC BY 4.0 license.

Disclaimer

Use this glossary at your own risk. Despite all passion and care that went into producing this book, I, Jens Oliver Meiert, assume no liability for errors or omissions in its contents. All information is subject to change and provided “as is,” with no guarantees of completeness, accuracy, or usefulness.

This all being said: Enjoy. Web Development is a great field.

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