Jens Oliver Meiert

The Web Development Glossary (More Than 2,000 Key Terms for Developers)

Post from April 7, 2020 (โ†ป June 21, 2022), filed under .

If you want to learn or master Web Development, perhaps youโ€™ll enjoy the most comprehensive glossary the field may have to offer.

I would recommend this not just for developers, but for anyone working in a software development team because everyone in the team needs to be aware of the concepts. This will help come up with better solutions and follow best practices.

โ€ฆsay readers at Reedsy.

Format Ebook (EPUB, MOBI, PDF)
Price $13.99 (minimum $9.99)
Preview Select chapters (PDF, 451 KB)
Length 340 pages (PDF)
Language English
License CC BY-SA 4.0 (Attribution-ShareAlike 4.0 International)
Sellers Apple Books
Google Play Books
Version 1.4.21 (2022)

Web Development is a large field. It takes a lot of time, practice, and discipline to master even part of it. Web Development is so large that many abstractions are being used, with design frameworks, HTML/CSS frameworks, JavaScript frameworks, and DevOps tooling making it possible to write complex applications without understanding the mechanics. This has always been like thatโ€”only the abstractions have changed from WYSIWYG editors to the โ€œone size fits allโ€ frameworks weโ€™re surrounded by now.

The cover of โ€œThe Web Development Glossary.โ€

The situation it presents us with is as interesting as it is challenging, for while it has traditionally been easy to become a web developer, it has also been hardโ€”requiring much studying, practicing, and learningโ€”to become a good web developer. Nowadays, with Web Development consisting of many subdisciplinesโ€”HTML and CSS and their optimizations, JavaScript, accessibility, security, performance, code maintainability and quality, internationalization and localization and much moreโ€”it may even be impossible to become a good web developer, that is, a good web developer in all the subdisciplines.

These are observations, however, and no judgment: Itโ€™s a quality of the field to wield so much power, to have so much depth, and still be so inviting. And inviting it really is, for there are many ways to enter Web Development. There are tons of introductions, tutorials, how-tos, and articles, fora and communities, courses and classes and videos and webinars and anything anyone with any learning preference could ever need.

What has been missing, however, is a comprehensive glossary. Not an index of different HTML elements and CSS properties and JavaScript methods, but a glossary of all the major, the key terms used. In Web Development, but also the relevant neighboring fields. The Web Development Glossary is filling this void: a living book that maps the entire landscape, that helps define and explain it.

If you donโ€™t know me, Iโ€™m Jens, and Iโ€™m a web developer of 21 years experience who loves and hates (but mostly loves) the field. What I love are its power and all the possibilities it gives us, as well as the challenges of its never-ending depth and complexity. Thatโ€™s why at the end of last year, I started working on The Web Development Glossary. I collected a few hundred terms. I reached 800 swiftly. Then 1,000. 1,600. 1,900. And now, for release, almost 2,000. Almost 2,000 explanations, some drawing from my own knowledge and research, a good part from the MDN Web Docs, and a great number from Wikipedia, which then meant a great investment to check, normalize, and improve, leading to a slightly better MDN Web Docs Glossary, a slightly better Wikipedia, and a certainly better (and just as generously licensed) glossary.

It was a lot of work to prepare, it will require more work to update and grow, but itโ€™s finally available, so please enjoy: The Web Development Glossary.


The Web Development Glossary is probably the largest of its kind. With more than 2,000 terms and explanations it 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.

The glossary then goes beyond web development, touching on 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, inspiring the curiosity to learn more about the Web and the people creating and using it. And still it is a glossary, of a couple of thousand terms for developers, leaning on (and giving back to) Wikipedia and the MDN Web Docs.

โ†’ This is the book if you choose to extend and validate your web and software development knowledge.

All ebook formats, with updates, at Leanpub.

โง I thank Wikipedia, the MDN Web Docs, and all their contributors for the great foundation they have laid that made it a lot more efficient to build the glossary. I then thank Gabriele Kretzschmar for review of the manuscript, and Ganesh Subramanian and Yaroslav Kiyenko for advice on book details. This has been a very special project for me, one which I now hope contributes to making the field, the field of Web Development, a tiny little more accessible.

Please have a look and check out the first edition of The Web Development Glossary.

Glossary Terms

The following terms have been covered by the glossary as of April 24, 2020 [it was since extended by many hundreds more terms]:

A List Apart ยท A/B testing ยท A11Y ยท AAA ยท Above the fold ยท Abstract Data Type ยท Abstraction ยท ACM ยท ACT ยท Action item ยท ActiveX ยท Accelerated Mobile Pages ยท Acceptance testing ยท Access control ยท Accessibility ยท Accessibility Conformance Testing ยท Accessibility Object Model ยท Accessibility tree ยท Accessible Rich Internet Applications ยท ActionScript ยท Active Server Pages ยท Active Users ยท Adaptive ยท Adaptive loading ยท Addon ยท Adobe Flash ยท ads.txt ยท ADT ยท Advanced Package Tool ยท Affordance ยท Agile ยท AJAX/Ajax ยท ALA ยท ALGOL ยท Algorithm ยท Algorithmic Language ยท Almost strict mode ยท Amaya ยท Amazon Silk ยท Amazon Web Services ยท AMD ยท American National Standards Institute ยท American Standard Code for Information Interchange ยท AMP ยท Analytics ยท Anchor ยท Angular ยท AngularJS ยท Animation ยท Anonymous block box ยท Anonymous block element ยท Anonymous function ยท Anonymous inline box ยท Anonymous inline element ยท Anonymous text ยท ANSI ยท Anti-pattern ยท AOM ยท Apache ยท Apache HTTP Server ยท Apache Tomcat ยท API ยท App ยท App shell ยท Apple Safari ยท Applet ยท Application ยท Application Programming Interface ยท APT ยท AR ยท Argument ยท ARIA ยท ARIA roles ยท Arrange, Act, Assert ยท Array ยท Arrow function ยท ASCII ยท ASI ยท ASP ยท ASP.NET ยท Aspect ratio ยท Assignment ยท Assistive technology ยท Assistive Technology Service Provider Interface ยท Association for Computing Machinery ยท Asynchronous ยท Asynchronous Module Definition ยท Asynchronous JavaScript and XML ยท at ยท AT ยท at-rule ยท AT-SPI ยท ATAG ยท Atom ยท Atomic CSS ยท Attribute ยท Attribute minimization ยท Augmented Reality ยท Authentication ยท Authoring Tool Accessibility Guidelines ยท Authorization ยท Automagic ยท Automatic Semicolon Insertion ยท Automation ยท Autonomous custom element ยท AWS ยท Babel ยท Backend ยท Backlink ยท Bad Neighborhood ยท Bandwidth ยท Banner ยท Base64 ยท Bash ยท Basic Multilingual Plane ยท BDD ยท Behavior ยท Behavior-Driven Development ยท Below the fold ยท BEM ยท Best practice ยท Bรฉzier curve ยท BHO ยท Bidirectional ยท Bidi ยท Big Bang ยท Big integer ยท Big O notation ยท Binary chop ยท Binary number ยท Binary search algorithm ยท Binding ยท Bitmap ยท BITV ยท Black hat ยท Black-box testing ยท Blacklist ยท Blink ยท Blisk ยท Block ยท Block box ยท Block container ยท Block container box ยท Block container element ยท Block element ยท Block Element Modifier ยท Block formatting context ยท Block-level box ยท Block-level element ยท Blog ยท Blogging ยท Blogosphere ยท BMP ยท BOM ยท Bookmark ยท Bookmark icon ยท Boolean ยท Bootstrap ยท Border ยท Bottom-posting ยท Bounce rate ยท Bound variable ยท Boundary value problem ยท Bounding box ยท Bourne shell ยท Bower ยท Box ยท Box model ยท Box model hack ยท Boyscout Rule ยท Bracket notation ยท Braille (โ ƒโ —โ โ Šโ ‡โ ‡โ ‘) ยท Branch ยท Branch predication ยท Branching ยท BREAD ยท Breadcrumb ยท Broken link ยท Brotli ยท Browse, Read, Edit, Add, Delete ยท Browser ยท Browser detection ยท Browser engine ยท Browser extension ยท Browser Helper Object ยท Browser sniffing ยท Browser testing ยท Browser War ยท Browsing ยท Browsing context ยท Buffer ยท Bug ยท Bug tracking system ยท Bugfix ยท Bugzilla ยท Build Verification Test ยท Bundling ยท BVT ยท Byte Order Mark ยท CA ยท Cache ยท Call stack ยท Call to Action ยท Callback ยท Canonical equivalence ยท Canonical link ยท Canonical Name ยท Canvas ยท Card sorting ยท Caret ยท Carousel ยท Cart ยท Cascade ยท Cascading HTML Style Sheets ยท Cascading Style Sheets ยท Case ยท catch ยท CBD ยท CBSE ยท CCT ยท CD ยท CDN ยท Certificate ยท Certificate Authority ยท CGI ยท Chaining ยท Change list ยท Change set ยท Changeset ยท Chaos engineering ยท Character ยท Character encoding ยท Character entity reference ยท Character reference ยท Character set ยท Charset ยท Chrome ยท Chrome Custom Tabs ยท Chromium ยท CHSS ยท CI ยท Cipher ยท CL ยท Class ยท CLI ยท Click ยท Click-Through Rate ยท Clickjacking ยท Client ยท Client Hints ยท Client side ยท Cloaking ยท Clone detection ยท Closure ยท Cloud ยท Cloud computing ยท Cloud storage ยท CLS ยท Cluster ยท CMS ยท CMYK ยท CNAME ยท CNAME cloaking ยท Coalescing ยท CoC ยท Code ยท Code coverage ยท Code debt ยท Code golf ยท Code of Conduct ยท Code point ยท Code refactoring ยท Code review ยท Code splitting ยท Codeline ยท CodePen ยท Coding by Convention ยท Coding guidelines ยท CoffeeScript ยท Collapsed margin ยท Color blindness ยท Color management ยท Comma-Separated Values ยท Command ยท Command-Line Interface ยท Command-Query Separation ยท Comment ยท Common Gateway Interface ยท CommonJS ยท Community of Practice ยท Compared to what? ยท Compass ยท Compatibility ยท Compatibility equivalence ยท Compatibility mode ยท Compiler ยท Compiling ยท Component ยท Component library ยท Component-Based Development ยท Component-Based Software Engineering ยท Compression ยท Concurrent Versioning System ยท Concurrent Versions System ยท Conditional ยท Conditional Comments ยท Cone of Uncertainty ยท Confidence testing ยท Confidentiality Agreement ยท Conflict of interest ยท Console ยท Constant ยท Constructor ยท Container ยท Containerization ยท Containing block ยท Content ยท Content box ยท Content Delivery Network ยท Content Management System ยท Content network ยท Content Security Policy ยท Context switch ยท Continuous Delivery ยท Continuous Deployment ยท Continuous Integration ยท Continuous Media ยท Contrast ยท Control flow ยท Convention over Configuration ยท Cookie ยท Cookie banner ยท Cookie consent ยท CoP ยท Corporate Design ยท Corporate Identity ยท CORS ยท Cost-per-click ยท Coupling ยท CPC ยท CQS ยท Craft ยท CRAP ยท Crawler ยท Crawling ยท Create, Read, Update, Delete ยท Create, Replicate, Append, Process ยท CRM ยท cron ยท Cron job ยท Crontab ยท Cross-Origin Resource Sharing ยท Cross-Site Request Forgery ยท Cross-Site Scripting ยท CRUD ยท CSCS ยท CSP ยท CSRF ยท CSS ยท CSS framework ยท CSS lock ยท CSS Modules ยท CSS Object Model ยท CSS Zen Garden ยท CSS-Tricks ยท CSSOM ยท CSV ยท CTA ยท CTR ยท Cumulative Layout Shift ยท Custom element ยท Custom property ยท Customer Relationship Management ยท Customized built-in element ยท Customized Scripting in C# ยท Cutting the mustard ยท CVS ยท Cyan, Magenta, Yellow, and Key ยท Cycle time ยท /dev/null ยท D3.js ยท Daemon ยท Daily Active Users ยท Daily Scrum ยท Dark Mode ยท Dark pattern ยท Darknet ยท Dart ยท Data ยท Data Control Language ยท Data Definition Language ยท Data Manipulation Language ยท Data Query Language ยท Data Stream Management System ยท Data type ยท Data visualization ยท Database ยท Database index ยท Database language ยท Database Management System ยท DAU ยท DAVE ยท DBC ยท DBMS ยท DCE ยท DCL ยท DCVS ยท DDL ยท DDoS ยท Dead code elimination ยท Debugging ยท Declaration ยท Declaration block ยท Decoration ยท Decryption ยท Deep Web ยท Defect ยท Defect tracking system ยท Definition of โ€œDoneโ€ ยท Delete, Add, View, Edit ยท Demilitarized Zone ยท Denial of Service ยท Deno ยท Dependency ยท Dependency injection ยท Dependency Inversion Principle ยท Deployment ยท Deprecated ยท Deprecation ยท Design ยท Design by Contract ยท Design language ยท Design system ยท Design strategy ยท Design vocabulary ยท Destructuring ยท Developer Experience ยท Developer Tools ยท Development and operations ยท Development Team ยท Device pixel ยท DevOps ยท DHTML ยท Dialog box ยท Digital Rights Management ยท Directionality ยท Display advertising ยท Display resolution ยท Distributed Concurrent Versions System ยท Distributed Version Control System ยท Dither ยท Divitis ยท DML ยท DMZ ยท DNS ยท DocBook ยท Doctype ยท Document directive ยท Document Object Model ยท Document Style Semantics and Specification Language ยท Document type declaration ยท Document Type Definition ยท Documentation ยท Dojo ยท DOM ยท Domain ยท Domain expert ยท Domain name ยท Domain Name Service ยท Domain Name System ยท Domain sharding ยท Donโ€™t Repeat Yourself ยท Doorway page ยท DoS ยท Dot file ยท Dot notation ยท Dot-agnostic ยท Double ยท Downtime ยท DQL ยท Dreamweaver ยท Driver ยท DRM ยท DRY ยท DSMS ยท DSSSL ยท DTD ยท Duck typing ยท Dup ยท Duplicate code ยท DVCS ยท DX ยท Dynamic ยท Dynamic HTML ยท Dynamic password ยท Dynamic typing ยท Dyslexia ยท E-commerce ยท E2E ยท EBCDIC ยท EBM ยท Eclipse ยท ECMA ยท Ecma International ยท ECMAScript ยท ECT ยท Edge ยท Editor ยท EditorConfig ยท EFF ยท Effective Connection Type ยท Effectiveness ยท Efficiency ยท Electron ยท Electronic Frontier Foundation ยท Element ยท else ยท Em ยท Emacs ยท Email ยท Email address ยท Embedded content ยท EME ยท Empiricism ยท Empty element ยท Empty string ยท Encapsulation ยท Encrypted Media Extensions ยท Encryption ยท End of line ยท End tag ยท End of file ยท End-to-end testing ยท Entity ยท Entity graph ยท Entity reference ยท EOF ยท EOL ยท Epic ยท Error ยท ES ยท Ethics ยท Etiquette ยท European Computer Manufacturers Association ยท Event ยท Event handler ยท Evidence-Based Management ยท Exception ยท Exception handling ยท Exception handling syntax ยท Exit code ยท Exit status ยท Express ยท Extended Binary Coded Decimal Interchange Code ยท Extensible HyperText Markup Language ยท Extensible Markup Language ยท Extensible Stylesheet Language ยท Extensible Stylesheet Language Transformations ยท External ยท Extreme Programming ยท Fallback ยท False negative ยท False positive ยท Falsy ยท Fat footer ยท Favicon ยท Favorite ยท FCP ยท Feature phone ยท Feed ยท Feed reader ยท FID ยท FIFO ยท File ยท File manager ยท File system ยท File Transfer Protocol ยท File-locking ยท Fingerprinting ยท Firebird ยท Firefox ยท First Contentful Paint ยท First CPU Idle ยท First In, First Out ยท First Input Delay ยท First Interactive ยท First Meaningful Paint ยท First Paint ยท First-Class Function ยท First-Order Function ยท Fittsโ€™ Law ยท Fixed ยท Flash ยท Flash of Faux Text ยท Flash of Invisible Text ยท Flash of Unstyled Content ยท Flash of Unstyled Text ยท Flash Player ยท Flex ยท Flexbox ยท Float ยท Flock ยท FLOSS ยท Flow content ยท Flow of control ยท Fluent Design System ยท Fluid ยท FMP ยท FOFT ยท Fold ยท FOIT ยท Folksonomy ยท Font ยท Font block period ยท Font failure period ยท Font swap period ยท for ยท foreach ยท Fork ยท Form ยท Formatting context ยท Formatting Output Specification Instance ยท FOSI ยท FOSS ยท FOUC ยท FOUT ยท FPS ยท Fragment identifier ยท Frame ยท Frame rate ยท Frames per Second ยท Framework ยท Frameset ยท Free and Open Source Software ยท Free Software Foundation ยท Free variable ยท Frontend ยท FrontPage ยท fs ยท FSF ยท FTP ยท Fugu ยท Full Service ยท Full Stack ยท Full stack developer ยท Function ยท Function binding ยท Functional programming ยท Functional testing ยท .gitignore ยท Gamma ยท Garbage collection ยท GDPR ยท Gecko ยท General Data Protection Regulation ยท General Image Manipulation Program ยท GIF ยท GIMP ยท Git ยท GitHub ยท GitLab ยท Global ยท Global object ยท Global scope ยท Global variable ยท Glyph ยท GNU ยท GNU General Public License ยท GNU Project ยท Go ยท Goanna ยท Golang ยท Google Chrome ยท Google Web Server ยท Gopher ยท GPL ยท GPU ยท Graceful Degradation ยท Grapheme ยท Graphic ยท Graphical User Interface ยท Graphics Interchange Format ยท Graphics Processing Unit ยท GraphQL ยท Greeking ยท Grid ยท Grid computing ยท Grid track ยท Guetzli ยท gulp ยท gulp.js ยท Gutter ยท GUI ยท GWS ยท gzip ยท .htaccess ยท .htpasswd ยท Hackathon ยท Hacker ยท Haml/HAML ยท Handlebars ยท Hard reset ยท Hash ยท Hash function ยท Hash table ยท Hashbang ยท Hashtag ยท hasLayout ยท HCI ยท HDD ยท Heading content ยท Headless ยท HEIC ยท HEIF ยท Helper class ยท Hickโ€™s Law ยท Hick-Hyman Law ยท Hidden Web ยท High Efficiency Image Coding ยท High Efficiency Image File Format ยท Higher-Order Component ยท Higher-Order Function ยท Hit ยท HITS ยท HOC ยท Hoisting ยท Holey ยท Home page ยท Home Page Reader ยท Home screen ยท Homepage ยท HomeSite ยท Hooking ยท Hop limit ยท Host ยท Houdini ยท HPR ยท HSL ยท HSTS ยท HSV ยท HTML ยท HTML Abstraction Markup Language ยท HTML template ยท HTML 5 ยท HTML/CSS framework ยท HTML5 ยท HTML5 Boilerplate ยท HTTP ยท HTTP method ยท HTTP status code ยท HTTP Strict Transport Security ยท HTTP/2 ยท httpd.conf ยท HTTPS ยท HTTPS Everywhere ยท Hue, Saturation, Lightness ยท Hue, Saturation, Value ยท Human-Computer Interaction ยท Hydration ยท Hyperlink ยท Hyperlink-Induced Topic Search ยท Hypertext ยท HyperText Markup Language ยท Hypertext Preprocessor ยท Hypertext Transfer Protocol ยท Hypertext Transfer Protocol Secure ยท Hypothesis-Driven Development ยท !important ยท I/O ยท I18N ยท IA ยท IaaS ยท IAB ยท IaC ยท IANA ยท ICANN ยท Icon ยท Icon font ยท ID ยท IDE ยท Identifier ยท IE ยท IETF ยท if ยท Iframe ยท IIFE ยท IIS ยท Image ยท Image map ยท Image replacement ยท IMAP ยท Immediately Invoked Function Expression ยท Immutable ยท In-App Browser ยท Inclusive Design ยท Increment ยท Indexed color ยท Indexed Database ยท IndexedDB ยท Indexing ยท Industrial Design ยท Infinite scrolling ยท Information Architecture ยท Information Design ยท Information foraging ยท Information overload ยท Information retrieval ยท Information scent ยท Information Security ยท Infosec ยท Infrastructure as a Service ยท Infrastructure as Code ยท Inheritance ยท Inline ยท Inline box ยท Inline element ยท Inline formatting context ยท Inline replying ยท Inline-level box ยท Inline-level element ยท Input/Output ยท Instant Articles ยท Integer ยท Integrated Development Environment ยท Intellectual Property ยท IntelliJ IDEA ยท Intent to Implement ยท Intent to Prototype ยท Interaction Design ยท Interaction Design Association ยท Interactive Advertising Bureau ยท Interactive content ยท Interface ยท Interleaved posting ยท Internal ยท International Organization for Standardization ยท Internationalization ยท Internationalized Resource Identifier ยท Internet ยท Internet Assigned Numbers Authority ยท Internet Corporation for Assigned Names and Numbers ยท Internet Engineering Task Force ยท Internet Explorer ยท Internet Information Services ยท Internet Message Access Protocol ยท Internet Protocol ยท Internet Relay Chat ยท Internet Resource Locator ยท Internet Service Provider ยท Internet Society ยท Interoperability ยท Intersection Observer ยท Interstitial ยท Intranet ยท Intrinsic size ยท Inversion of Control ยท Inverted Triangle CSS ยท IoC ยท iOS ยท IP ยท IP address ยท IP telephony ยท IPv4 ยท IPv6 ยท IRC ยท IRI ยท IRL ยท ISO ยท ISOC ยท ISP ยท ITCSS ยท IxD ยท IxDA ยท Jakobโ€™s Law ยท JAMStack ยท Jank ยท JAR ยท Jasmine ยท Java ยท Java applet ยท Java archive ยท Java Database Connectivity ยท Java servlet ยท JavaScript ยท JavaScript framework ยท JavaScript library ยท JavaScript Object Notation ยท JavaScript Object Notation for Linked Data ยท JavaScript XML ยท JavaServer Pages ยท JAWS ยท JDBC ยท Jekyll ยท Jetty ยท Jira ยท JIT ยท JIT compiler ยท Job Access With Speech ยท Joint Photographic Experts Group ยท JPEG ยท JPG ยท jQuery ยท JS ยท JScript ยท JSLint ยท JSON ยท JSON Feed ยท JSON Web Encryption ยท JSON Web Signature ยท JSON Web Token ยท JSON-LD ยท JSP ยท JSX ยท Just in Time ยท Just-in-time compilation ยท JWS ยท JWT ยท K-Meleon ยท Kanban ยท Kerberos ยท Kerning ยท Key ยท Key Performance Indicator ยท Key-value database ยท Keyword ยท KHTML ยท Knowledge Graph ยท Konqueror ยท KPI ยท L10N ยท Lambda abstraction ยท Lambda expression ยท LAMP ยท Landing page ยท Language ยท Largest Contentful Paint ยท Last In, First Out ยท Latency ยท LaTeX ยท Launch ยท Law of Conservation of Complexity ยท Layout ยท Layout engine ยท Layout table ยท Lazy loading ยท LCP ยท LDAP ยท Lead time ยท Leading ยท Lean ยท Left-to-Right ยท Legibility ยท Less/LESS ยท Letโ€™s Encrypt ยท Letter-spacing ยท Library ยท LIFO ยท Ligature ยท Light Mode ยท Lightweight Directory Access Protocol ยท Line box ยท Line ending ยท Line feed ยท Line terminator ยท Lines of Code ยท Link ยท Link rot ยท Linked Data ยท Linter ยท Linting ยท Linux ยท Linux Standard Base ยท Linux, Apache, MySQL, PHP/Perl/Python ยท Liquid ยท Lite Mode ยท Literal ยท Littleโ€™s Law ยท Load time ยท LOC ยท Local ยท Local-part ยท Local scope ยท Local variable ยท Locale ยท Localization ยท Lock file ยท Log file ยท Logging ยท Logical properties ยท Long task ยท Long-Term Support ยท Loop ยท Lorem ipsum ยท Lossless ยท Lossy ยท LSB ยท LTR ยท LTS ยท Lynx ยท Mac OS ยท Machine Learning ยท macOS ยท macOS, Apache, MySQL, PHP/Perl/Python ยท Macromedia Flash ยท Mail ยท Main thread ยท Maintainability ยท Maintenance ยท Makefile ยท MAMP ยท Margin ยท Margin collapsing ยท Markdown ยท Marketing ยท Markup ยท Markup language ยท Masthead ยท Material Design ยท Mathematical markup language ยท Mathematical Markup Language ยท MathML ยท MAU ยท MD2 ยท MD4 ยท MD5 ยท MD6 ยท MDL ยท MEAN ยท Media ยท Media query ยท Media type ยท Medium integer ยท Mega menu ยท Memoization ยท Menu ยท Merge request ยท Merging ยท Message Digest ยท Meta-element ยท Metadata ยท Metadata content ยท Method ยท Method stub ยท Metro ยท Microformat ยท Microsite ยท Microsoft Design Language ยท Microsoft Edge ยท Middleware ยท MIME ยท MIME type ยท Minification ยท Minifier ยท Minimum Viable Product ยท MIP ยท Mixin ยท ML ยท Mobile ยท Mobile First ยท Mobile Instant Pages ยท Mobilegeddon ยท Mocha ยท Modal ยท Model-View-Controller ยท Model-View-Viewmodel ยท Modernizr ยท Modular design ยท Module ยท Monolith ยท Monolithic application ยท Monorepo ยท Monthly Active Users ยท Mosaic ยท Moving Picture Experts Group ยท Mozilla Firefox ยท MPEG ยท MR ยท MSHTML ยท MSIE ยท Multimedia ยท Multiple inheritance ยท Multipurpose Internet Mail Extensions ยท Mustache ยท Mutable ยท Mutation ยท MVC ยท MVP ยท MVVM ยท MySQL ยท .NET ยท .NET Framework ยท n-based indexing ยท Name binding ยท Namespace ยท NaN ยท Native ยท Navigation ยท Navigator ยท NDA ยท Nesting ยท Net Promoter Score ยท Netscape 4 ยท Netscape Navigator ยท Network ยท Network packet ยท Newbie ยท Newline ยท News aggregator ยท Nexus ยท NGINX ยท Night Mode ยท Node ยท Node Package Manager ยท Node.js ยท Non-Disclosure Agreement ยท Noob ยท Normalization ยท Normalize.css ยท Normative ยท NoSQL ยท Not a Number ยท npm ยท NPS ยท Null ยท Null device ยท Null pointer ยท Number ยท Number sign ยท Numeral ยท Numeric character reference ยท Numerical digit ยท Nuxt.js ยท Obfuscation ยท Object ยท Object-Oriented CSS ยท Object-Oriented Programming ยท Objectives and Key Results ยท Observer ยท Observer pattern ยท Offline ยท Offline First ยท OGP ยท OKR ยท One-based indexing ยท One-Time Password ยท OOCSS ยท OOP ยท Open Graph Protocol ยท Open Source ยท Open Web Application Security Project ยท Opera ยท Operand ยท Operating System ยท Operator ยท Optimization ยท Optional markup ยท Orca ยท Origin ยท Orphan ยท Orthogonality ยท OS ยท OSI Model ยท OTA ยท OTP ยท Outline ยท Over the Air ยท OWASP ยท package.json ยท package-lock.json ยท Packed ยท Packet ยท Padding ยท Page ยท Page impression ยท Page prediction ยท Page Quality ยท PageRank ยท PageSpeed ยท Page view ยท Pair programming ยท Palpable content ยท Paradigm ยท Parallax scrolling ยท Parameter ยท Pareto Principle ยท Parkinsonโ€™s Law ยท Parser ยท Parsing ยท Patch ยท Path ยท PATH ยท Pattern ยท Pattern library ยท Pave the cowpaths ยท Pay-per-click ยท Payload ยท PBI ยท PDF ยท Peer review ยท Pen test ยท Penetration testing ยท Perceivable, Operable, Understandable, and Robust ยท Perceived performance ยท Percent encoding ยท Performance ยท Performance budget ยท Performance indicator ยท Perl ยท Permalink ยท Persona ยท Personal Home Page ยท PhantomJS ยท Phoenix ยท Photoshop ยท PHP ยท PhpStorm ยท Phrasing content ยท Ping ยท Pinging ยท Pixel ยท Pixel tag ยท Pixel-perfect ยท Placeholder ยท Placeholder text ยท Plain-text ยท Plane ยท Plugin ยท PNG ยท Pointer ยท Pointing device ยท Polyfill ยท Polymer Project ยท POP ยท Pop-under ยท Pop-up ยท Port ยท Portable Document Format ยท Portable Network Graphics ยท Portal ยท Post mortem ยท Post Office Protocol ยท PostCSS ยท Postelโ€™s Law ยท POUR ยท PowerShell ยท PPC ยท PQ ยท PR ยท Preact ยท Predication ยท Prefetching ยท Premature optimization ยท Prerendering ยท Presentation ยท Presto ยท Primitive ยท Principal box ยท Print style sheet ยท Privacy ยท Product Backlog ยท Product Backlog Item ยท Product Owner ยท Programming language ยท Progressive Enhancement ยท Progressive Web App ยท Promise ยท Prop ยท Property ยท Protocol ยท Prototype ยท Prototyping ยท PRPL ยท Pseudo-class ยท Pseudo-code ยท Pseudo-element ยท Pull request ยท Push notification ยท Push technology ยท PV ยท PWA ยท Python ยท QA ยท QC ยท qooxdoo ยท Quality ยท Quality Assurance ยท Quality Control ยท Quantity query ยท Query ยท Query language ยท QUIC ยท Quick UDP Internet Connection ยท Quirks mode ยท Race condition ยท Rails ยท Raku ยท Random variable ยท Ranking ยท Raster image ยท RCS ยท RDBMS ยท RDF ยท RDF Site Summary ยท RDSMS ยท React ยท Reactive Extensions for JavaScript ยท Reactive programming ยท ReactJS ยท Read the Fucking Manual ยท Read-Eval-Print Loop ยท Readability ยท Reading disorder ยท README ยท Real User Monitoring ยท Really Simple Syndication ยท Recidivism ยท Recommendation ยท Recursion ยท Red, Green, and Blue ยท Redesign ยท Redirect ยท Redundancy ยท Redux ยท Refactoring ยท Reference error ยท Referential opacity ยท Referential transparency ยท Reflow ยท Regex ยท Regular expression ยท Rehydration ยท Relational Data Stream Management System ยท Relational database ยท Relational Database Management System ยท Relational model ยท Relaunch ยท Rem ยท Render tree ยท Rendering ยท Rendering engine ยท Repo ยท Repository ยท REPL ยท Replaced element ยท Representational State Transfer ยท Request ยท Request for Comments ยท Request header ยท Request method ยท RequireJS ยท Reset ยท Reset style sheet ยท Resolution ยท Resource Description Framework ยท Response ยท Response header ยท Responsive design ยท Responsive web design ยท Responsiveness ยท REST ยท Restricted production ยท Revision control ยท Revision Control System ยท RFC ยท RGB ยท RIB ยท Rich Site Summary ยท Rich Text Format ยท Right-to-Left ยท Roadmap ยท Robots exclusion standard ยท robots.txt ยท Robustness Principle ยท Root ยท Root directory ยท Root element ยท Root em ยท Root node ยท Rooting ยท Round-Trip Delay Time ยท Round-Trip Time ยท Router ยท Routine ยท Routing ยท Routing Information Base ยท Routing table ยท RPM ยท RPM Package Manager ยท RSS ยท RTD ยท RTF ยท RTFM ยท RTL ยท RTT ยท Rubber-ducking ยท Ruby ยท Ruby on Rails ยท Rule ยท Rule set ยท RUM ยท Runtime compilation ยท RWD ยท RxJS ยท Safari ยท Same origin ยท Sandbox ยท Sass ยท SassScript ยท SAST ยท Scalable and Modular Architecture for CSS ยท Scalable Vector Graphics ยท Scalar ยท Scaled Scrum ยท SCM ยท Scope ยท Scoped styles ยท Screen reader ยท Script ยท Scripting language ยท Scroll Snap ยท Scrolling ยท Scrollport ยท Scrum ยท Scrum Master ยท Scrum Team ยท Scrum Values ยท SCSS ยท SEA ยท SeaMonkey ยท Search Engine Advertising ยท Search engine indexing ยท Search Engine Marketing ยท Search Engine Optimization ยท Search Engine Results Page ยท Searching ยท Section 508 ยท Sectioning content ยท Secure Shell ยท Secure Sockets Layer ยท Security ยท Security hacker ยท security.txt ยท Selector ยท Selenium ยท SEM ยท Semantic Versioning ยท Semantic Web ยท Semantics ยท SemVer ยท SEO ยท Separation of Concerns ยท SERP ยท Server ยท Server cluster ยท Server farm ยท Server logs ยท Server push ยท Server side ยท Server-Side Rendering ยท Service Level Agreement ยท Service Level Expectation ยท Service worker ยท Set ยท SFTP ยท SGML ยท Shadow DOM ยท Shadow host ยท Shadow root ยท Shadow tree ยท Shebang ยท Shell ยท Shim ยท Shockwave Flash ยท Shortcut icon ยท Shorthand ยท SI ยท Signed HTTP Exchanges ยท Silk ยท Simple Mail Transfer Protocol ยท Simple Object Access Protocol ยท Single Responsibility Principle ยท Single-Page Application ยท Site ยท Site map ยท Sitemaps ยท Sketch ยท Skin ยท SLA ยท SLE ยท Sliding Doors ยท SLOC ยท Sloppy mode ยท Slot ยท Slug ยท SMACSS ยท Small integer ยท Smashing Magazine ยท SME ยท Smi ยท SMIL ยท SMTP ยท Smoke testing ยท Snap position ยท SOAP ยท SOC ยท Social Web ยท Soft launch ยท Soft opening ยท Software ยท Software crisis ยท Software development ยท Software framework ยท Software stack ยท Software testing ยท Solution stack ยท Source Code Management ยท Source Control Management ยท Source Lines of Code ยท SPA ยท Spacer ยท Spaghetti code ยท Spam ยท Spamdexing ยท Spamming ยท SPDY ยท Spec ยท Specification ยท Specificity ยท Speed Index ยท Spider ยท Splash screen ยท Spoofing ยท Spread ยท Sprint ยท Sprint Goal ยท Sprite ยท SQL ยท SQL injection ยท Squad ยท sRGB ยท SSG ยท SSH ยท SSH File Transfer Protocol ยท SSL ยท SSR ยท Stack ยท Stack Overflow ยท Stacking context ยท Stand-up ยท Standard ยท Standard Generalized Markup Language ยท standard Red Green Blue ยท Standards mode ยท Star ยท Star hack ยท Start page ยท Start tag ยท State ยท Static ยท Static Application Security Testing ยท Static Site Generator ยท Status code ยท Stream ยท Streaming media ยท Strict mode ยท String ยท Structure ยท Structured Query Language ยท Stub ยท Style guide ยท Style sheet ยท stylelint ยท Styling ยท Subject-Matter Expert ยท Subnav ยท Subnavigation ยท Subroutine ยท Subversion ยท SUIT CSS ยท Superuser ยท Support ยท Surface Web ยท Surfing ยท SVG ยท SVN ยท SXG ยท Symbol ยท Synchronized Multimedia Integration Language ยท Synchronous ยท Syndication ยท Syntax ยท Syntax analysis ยท syslog ยท Tab ยท Tab icon ยท Tabbed Document Interface ยท Table box ยท Table formatting context ยท Tachyons ยท Tag ยท Tag Management System ยท Tag soup ยท Tagging ยท Tailoring ยท tar ยท Tarball ยท Tcl ยท TCP ยท TDD ยท TDI ยท TDZ ยท Tech Lead ยท Tech Twitter ยท Technical debt ยท Technical Lead ยท Technical Program Manager ยท Technical standard ยท Technological Protection Measures ยท Telnet ยท Template ยท Template language ยท Template processor ยท Template system ยท Temporal Dead Zone ยท Ten-Second Rule ยท Terminal ยท Ternary operator ยท Teslerโ€™s Law ยท Test pyramid ยท Test-Driven Development ยท Testing ยท TeX ยท The Onion Router ยท Theme ยท Third party ยท this ยท Thread ยท Three-Click Rule ยท Time box ยท Time to First Byte ยท Time to Interactive ยท Time to Live ยท Timestamp ยท Tiny integer ยท TL ยท TLD ยท TLS ยท TMS ยท To-do ยท Toast ยท Todo ยท TOFU ยท Tomโ€™s Obvious, Minimal Language ยท Tomcat ยท TOML ยท Tooling ยท Top-Level Domain ยท Top-posting ยท Tor ยท Tor Browser ยท Tor network ยท Tor Project ยท TPM ยท Tracer code ยท Tracing ยท Tracking ยท Tracking pixel ยท Trade ยท Transcompiler ยท Transmission Control Protocol ยท Transpiler ยท Transport Layer Security ยท Tree-shaking ยท Trident ยท Trust on First Use ยท Trust Upon First Use ยท TrustRank ยท try ยท tryโ€ฆcatch ยท TTFB ยท TTI ยท TTL ยท TUFU ยท Turbo pages ยท Type ยท Type coercion ยท Type conversion ยท Type design ยท Type I error ยท Type II error ยท Type system ยท Typeface ยท TypeScript ยท Typography ยท UA ยท UAAG ยท UAT ยท UCD ยท UDD ยท UDJO ยท UDP ยท Uglification ยท UI ยท UI framework ยท UI redressing ยท UMD ยท UML ยท undefined ยท Underscore hack ยท Unicode ยท Unicode Consortium ยท Unified Modeling Language ยท Uniform Resource Characteristic ยท Uniform Resource Identifier ยท Uniform Resource Locator ยท Uniform Resource Name ยท Uninitialized pointer ยท Uninitialized variable ยท Unit testing ยท Universal Design ยท Universal Module Definition ยท Unix/UNIX ยท Unix philosophy ยท UPA ยท URC ยท URI ยท URL ยท URL encoding ยท URL forwarding ยท URL redirection ยท URL slug ยท URN ยท Usability ยท Usability inspection ยท Usability Professionals Association ยท Usability testing ยท Usenet ยท User ยท User acceptance testing ยท User agent ยท User Agent Accessibility Guidelines ยท User Datagram Protocol ยท User Experience ยท User Experience Professionals Association ยท User Interface ยท User story ยท User testing ยท User-Centered Design ยท User-Driven Development ยท Using Declarations Just Once ยท UTF-8 ยท UTF-16 ยท UTF-32 ยท Utility class ยท UX ยท UXPA ยท Validation ยท Validator ยท Value ยท Variable ยท Variable scope ยท VBA ยท Vector image ยท Velocity ยท Vendor prefix ยท Verification ยท Version control ยท Versioning ยท vi ยท Viewport ยท Vim ยท Virtual inheritance ยท Virtual Machine ยท Virtual Private Network ยท Virtual Reality ยท Virtualization ยท Visual Basic for Applications ยท Visual formatting model ยท Visual regression testing ยท Visual Studio Code ยท VM ยท Voice over IP ยท VoiceOver ยท VoiceXML ยท Void element ยท VoIP ยท VPN ยท VR ยท VRT ยท VS Code ยท Vue ยท Vue.js ยท VuePress ยท Vuex ยท W3C ยท WAF ยท WAI ยท WAMP ยท WAP ยท WAR ยท Wasm ยท WaSP ยท Waterfall ยท WAU ยท WCAG ยท WCAG Samurai ยท Web 2.0 ยท Web Accessibility Initiative ยท Web address ยท Web analytics ยท Web app ยท Web application ยท Web application archive ยท Web Application Framework ยท Web beacon ยท Web browser ยท Web bug ยท Web Bundles ยท Web component ยท Web content ยท Web Content Accessibility Guidelines ยท Web design ยท Web development ยท Web feed ยท Web font ยท Web forms ยท Web framework ยท Web Graphics Library ยท Web Hypertext Application Technology Working Group ยท Web IDL ยท Web indexing ยท Web Packaging ยท Web page ยท Web performance ยท Web Performance Optimization ยท Web resource ยท Web service ยท Web site ยท Web standard ยท Web standards movement ยท Web Standards Project ยท Web storage ยท Web tracking ยท Web typography ยท Web worker ยท WebAssembly ยท WebAuthn ยท WebGL ยท WebKit ยท Webkrauts ยท Weblog ยท WebM ยท WebP ยท webpack ยท WebPageTest ยท Website ยท WebSocket ยท WebStorm ยท WebView ยท Weekly Active Users ยท WET ยท What You See Is All You Get ยท What You See Is What You Get ยท WHATWG ยท while ยท White-box testing ยท Whitelist ยท Whitespace ยท WHOIS ยท Widow ยท Window-Eyes ยท Windows ยท Windows Aero ยท Windows, Apache, MySQL, PHP/Perl/Python ยท WIP ยท Wireframe ยท Wireless Application Protocol ยท Wireless Markup Language ยท WML ยท WORA ยท Work in Progress ยท Workaround ยท World Wide Web ยท World Wide Web Consortium ยท WorldWideWeb ยท WPO ยท Wrapper ยท Write Once, Run Anywhere ยท WWW ยท WYSIAYG ยท WYSIWYG ยท x-height ยท XForms ยท XHP ยท XHR ยท XHTML ยท XLink ยท XML ยท XML Schema Definition ยท XML User Interface Language ยท XMLHttpRequest ยท XP ยท XPath ยท XPointer ยท XQuery ยท XSD ยท XSL ยท XSLT ยท XSRF ยท XSS ยท XUL ยท Yahoo User Interface Library ยท YAML ยท YAML Ainโ€™t Markup Language ยท Yarn ยท yarn.lock ยท Yet Another Multicolumn Layout ยท YUI ยท Z shell ยท Zero-based indexing ยท Zero-indexed ยท ZIP ยท Zombie cookie ยท Zsh

Consult The Web Development Glossary for quick access to explanations to all these terms. And if you miss anything, please leave a suggestion. (Thank you!)

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About Me

Jens Oliver Meiert, on April 29, 2020.

Iโ€™m Jens Oliver Meiert, and Iโ€™m an engineering lead (currently manager for Developer Experience at LivePerson) and author. Iโ€™ve worked as a technical lead for Google, Iโ€™m close to W3C and WHATWG, and I write and review books for Oโ€™Reilly. I love trying things, sometimes including philosophy, art, and adventure. Here on I share some of my views and experiences.

If you have questions or suggestions about what I write, please leave a comment (if available) or a message.

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Cover: The Web Development Glossary.

Perhaps my most comprehensive book: The Web Development Glossary (2020). With explanations and definitions for literally thousands of terms from Web Development and related fields, building on Wikipedia as well as the MDN Web Docs. Available at Apple Books, Kobo, Google Play Books, and Leanpub.

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