Learn a new term:
- Copyleft
- Copyleft is a term, usually referring to a license, used to indicate that such license requires that redistribution of said work is subject to the same license as the original. Examples of copyleft licenses are the GNU GPL (for software) and the Creative Commons SA (Share Alike) licenses (for works of art).
Web technologies contain long lists of jargon and abbreviations that are used in documentation and coding. This glossary provides definitions of words and abbreviations you need to know to successfully understand and build for the web.
A
- Abstraction
- Accessibility
- Adobe Flash
- AJAX
- Algorithm
- API
- Apple Safari
- Application Context
- Argument
- ARIA
- ARPA
- Arpanet
- Array
- ASCII
- Asynchronous
- ATAG
- Attribute
B
- Bandwidth
- BiDi
- Blink
- Block
- Block (CSS)
- Block (scripting)
- Boolean
- Boot2Gecko
- Bounding Box
- Browser
- Browsing context
- buffer
C
- Cache
- Cacheable
- CalDAV
- Call stack
- Callback function
- Canonical order
- Canvas
- Card sorting
- CardDAV
- caret
- CDN
- Certificate authority
- Certified
- Challenge-response authentication
- Character
- Character encoding
- Chrome
- CIA
- Cipher
- Cipher suite
- Ciphertext
- Class
- Closure
- CMS
- Codec
- Compile
- Compile time
- Computer Programming
- Conditional
- Constant
- Constructor
- Control flow
- Cookie
- Copyleft
- CORS
- Crawler
- CRLF
- Cross Axis
- Cross-site scripting
- CRUD
- Cryptanalysis
- Cryptographic hash function
- Cryptography
- CSP
- CSRF
- CSS
- CSS preprocessor
D
- Data structure
- Decryption
- Denial of Service
- Descriptor (CSS)
- Deserialization
- Developer Tools
- DHTML
- Digest
- Digital certificate
- Distributed Denial of Service
- DMZ
- DNS
- Doctype
- Document directive
- document environment
- DOM
- Domain
- Domain name
- Dominator
- DoS attack
- DTD
- DTMF (Dual-Tone Multi-Frequency signaling)
- Dynamic programming language
- Dynamic typing
E
- ECMA
- ECMAScript
- Element
- Empty element
- Encapsulation
- Encryption
- Endianness
- Engine
- Entity
- Entity header
- Event
- Exception
- Expando
F
- Falsy
- Fetch directive
- Firefox OS
- firewall
- First-class Function
- Flex
- Flex Container
- Flex Item
- Flexbox
- Forbidden header name
- Forbidden response header name
- Fork
- FTP
- FTU
- Function
G
- Gaia
- Garbage collection
- Gecko
- General header
- GIF
- GIJ
- Git
- Global attribute
- Global object
- Global scope
- Global variable
- Gonk
- Google Chrome
- GPL
- GPU
- Graceful degradation
- Grid
- Grid Areas
- Grid Axis
- Grid Cell
- Grid Column
- Grid Lines
- Grid Row
- Grid Tracks
- Guard
- Gutters
- GZip compression
H
- Hash
- Head
- Header
- High-level programming language
- HMAC
- Hoisting
- Host
- Hotlink
- HPKP
- HSTS
- HTML
- HTML5
- HTTP
- HTTPS
- Hyperlink
- Hypertext
I
- I18N
- IANA
- ICANN
- ICE
- IDE
- Idempotent
- Identifier
- IDL
- IETF
- IIFE
- IMAP
- Immutable
- Index
- IndexedDB
- Information architecture
- Inheritance
- Instance
- Internet
- IP Address
- IPv4
- IPv6
- IRC
- ISO
- ISP
J
K
L
M
- Main Axis
- MathML
- Metadata
- Method
- Microsoft Edge
- Microsoft Internet Explorer
- Middleware
- mime
- MIME type
- MitM
- Mixin
- Mobile First
- Modem
- Modern web apps
- Modularity
- Mozilla Firefox
- Mutable
- MVC
N
- Namespace
- NaN
- NAT
- Native
- Navigation directive
- Netscape Navigator
- NNTP
- Node
- Node (DOM)
- Node (networking)
- Node.js
- non-normative
- Normative
- Null
- Number
O
P
- P2P
- PAC
- Parameter
- Parent object
- Parse
- Parser
- Percent-encoding
- PHP
- Pixel
- Placeholder names
- Plaintext
- PNG
- Polyfill
- Polymorphism
- POP3
- Port
- Preflight request
- Presto
- Primitive
- Privileged
- privileged code
- Progressive Enhancement
- Progressive web apps
- Property
- Property (CSS)
- Property (JavaScript)
- Protocol
- Prototype
- Prototype-based programming
- Proxy server
- Pseudo-class
- Pseudo-element
- Pseudocode
- Python
Q
R
- Random Number Generator
- Raptor
- Raster image
- RDF
- Recursion
- Reference
- Reflow
- Regular expression
- Rendering engine
- Repo
- Reporting directive
- Request header
- Response header
- Responsive web design
- REST
- RGB
- RIL
- Robots.txt
- RSS
- RTF
- rtl
- RTP
- RTSP
- Ruby
S
- Safe
- SCM
- Scope
- Script-supporting element
- SCTP
- SDP
- Search engine
- Second-level Domain
- Selector (CSS)
- Semantics
- SEO
- Serialization
- Server
- Session Hijacking
- SGML
- Shim
- Signature
- Signature (functions)
- Signature (security)
- SIMD
- Simple header
- Simple response header
- SISD
- SLD
- Sloppy mode
- Slug
- Smoke Test
- SMTP
- SOAP
- Specification
- SQL
- SQL Injection
- SRI
- SSL
- Stacking context
- State machine
- Statement
- Static typing
- String
- STUN
- SVG
- SVN
- Symbol
- Synchronous
- Syntax
- Syntax error
T
U
V
W
- W3C
- WAI
- WCAG
- Web standards
- WebDAV
- WebExtensions
- WebGL
- WebIDL
- WebKit
- WebM
- WebP
- WebRTC
- WebSockets
- WebVTT
- WHATWG
- World Wide Web
- Wrapper
X
Other
Contribute to the glossary
This glossary is a never ending work in progress. You can help improving it by writing new entries or by making the existing ones better. The easiest way to start is to hit the following button or to pick one of the suggested terms below.
- at-rule
- Attack
- Character set
- cryptosystem
- debug
- digital signature
- execution
- flex-direction
- fork
- GLSL
- Grid Container
- Interface
- Intrinsic size
- Library
- Memory management
- Public-key crytography
- routers
- RTP
- RTSP
- Self-Executing Anonymous Function
- Stylesheet
- Symmetric-key cryptography
- Vector image
If you want to know more on how to contribute to the glossary, check out the glossary documentation status page.
Join the Glossary community
Choose your preferred method for joining the discussion:
- IRC: #mdn (learn more)
- Contribute: See the doc status for more information
Document Tags and Contributors
Tags:
Contributors to this page:
chrisdavidmills,
SphinxKnight,
bunnybooboo,
kberov,
sebastien-bartoli,
jswisher,
klez,
Jeremie,
hbloomer,
Andrew_Pfeiffer,
Sheppy,
fscholz,
teoli,
Yecril,
wbamberg,
alispivak,
tregagnon,
rebloor,
ajinkya_p,
fossterer,
LauraHilliger,
shafiul,
thornet,
Oliver_Propst,
c2the3rd,
Ms2ger,
trevorh,
aw1231,
ethertank,
Seta00,
jenzed,
Bomfog,
Nelson_bolyard.com,
Nickolay,
Jorend,
GijsKruitbosch,
PWeilbacher,
Taken,
Okome,
Mgjbot,
Waldo,
MykMelez,
Callek,
cbiesinger
Last updated by:
chrisdavidmills,