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.
Note: If you'd prefer a web development glossary in book form, check out The Web Development Glossary (EPUB, MOBI, PDF). It’s a third-party glossary that includes the entries found here, and also adds a wide range of additional entries.
Glossary of Terms
Learn a new term:
- Prerender
- With prerendering, the content is prefetched and then rendered in the background by the browser as if the content had been rendered into an invisible separate tab. When the user navigates to the prerendered content, the current content is replaced by the prerendered content instantly.
A
B
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
- Character set
- Chrome
- CIA
- Cipher
- Cipher suite
- Ciphertext
- Class
- Client hints
- Closure
- CMS
- Code splitting
- Codec
- Compile
- Compile time
- Computer Programming
- Conditional
- Constant
- Constructor
- Continuous Media
- Control flow
- Cookie
- Copyleft
- CORS
- CORS-safelisted request header
- CORS-safelisted response header
- Crawler
- CRLF
- Cross Axis
- Cross-site scripting
- CRUD
- Cryptanalysis
- Cryptographic hash function
- Cryptography
- CSP
- CSRF
- CSS
- CSS Object Model (CSSOM)
- CSS pixel
- CSS preprocessor
D
- Data structure
- Database
- Decryption
- Delta
- Denial of Service
- Descriptor (CSS)
- Deserialization
- Developer Tools
- DHTML
- Digest
- Digital certificate
- Distributed Denial of Service
- DMZ
- DNS
- Doctype
- Document directive
- document environment
- DOM (Document Object Model)
- Domain
- Domain name
- Domain sharding
- Dominator
- DoS attack
- DTLS (Datagram Transport Layer Security)
- DTMF (Dual-Tone Multi-Frequency signaling)
- Dynamic programming language
- Dynamic typing
E
F
- Fallback alignment
- Falsy
- Favicon
- Fetch directive
- Fetch metadata request header
- Firefox OS
- firewall
- First contentful paint
- First CPU idle
- First input delay
- First interactive
- First Meaningful Paint
- First paint
- First-class Function
- Flex
- Flex Container
- Flex Item
- Flexbox
- Forbidden header name
- Forbidden response header name
- Fork
- Fragmentainer
- frame rate (FPS)
- FTP
- FTU
- Function
- Fuzz testing
G
H
I
J
K
L
M
N
O
P
- P2P
- PAC
- Packet
- Page load time
- Page prediction
- Parameter
- Parent object
- Parse
- Parser
- Payload body
- Perceived performance
- Percent-encoding
- PHP
- Pixel
- Placeholder names
- Plaintext
- PNG
- Polyfill
- Polymorphism
- POP3
- Port
- Prefetch
- Preflight request
- Prerender
- Presto
- Primitive
- Privileged
- privileged code
- Progressive Enhancement
- Progressive web apps
- Promise
- Property
- Property (CSS)
- Property (JavaScript)
- Protocol
- Prototype
- Prototype-based programming
- Proxy server
- Pseudo-class
- Pseudo-element
- Pseudocode
- Public-key cryptography
- Python
Q
R
- RAIL
- Random Number Generator
- Raster image
- RDF
- Real User Monitoring (RUM)
- Recursion
- Reference
- Reflow
- Regular expression
- Rendering engine
- Repo
- Reporting directive
- Request header
- Resource Timing
- Response header
- Responsive web design
- REST
- RGB
- RIL
- Robots.txt
- Round Trip Time (RTT)
- Routers
- RSS
- Rsync
- RTCP (RTP Control Protocol)
- RTF
- RTL (Right to Left)
- RTP (Real-time Transport Protocol) and SRTP (Secure RTP)
- RTSP: Real-time streaming protocol
- Ruby
S
- Safe
- Same-origin policy
- SCM
- Scope
- Screen reader
- Script-supporting element
- Scroll container
- Scrollport
- SCTP
- SDP
- Search engine
- Second-level Domain
- Secure Sockets Layer (SSL)
- Selector (CSS)
- Self-Executing Anonymous Function
- Semantics
- SEO
- Serialization
- Server
- Server Timing
- Session Hijacking
- SGML
- Shadow tree
- Shim
- Signature
- Signature (functions)
- Signature (security)
- SIMD
- Simple header
- Simple response header
- SISD
- Site
- Site map
- SLD
- Sloppy mode
- Slug
- Smoke Test
- SMPTE (Society of Motion Picture and Television Engineers)
- SMTP
- Snap positions
- SOAP
- SPA (Single-page application)
- Specification
- Speculative parsing
- Speed index
- SQL
- SQL Injection
- SRI
- Stacking context
- State machine
- Statement
- Static method
- Static typing
- Strict mode
- String
- STUN
- Style origin
- Stylesheet
- SVG
- SVN
- Symbol
- Symmetric-key cryptography
- Synchronous
- Syntax
- Syntax error
- Synthetic monitoring
T
U
V
W
X
Other
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