Client-Server architecture, 3-tier web architecture, HTTP protocol, DNS, URL structure, MIME types, web hosting.
HTML fundamentals, headings, paragraphs, links, lists, tables, images, div/span, character entities, URL encoding, frames.
HTML forms & input types, Canvas drawing API, audio/video embedding, form attributes, HTML vs XHTML.
CSS selectors, box model, specificity, display/float/overflow, colors, backgrounds, borders, margins, padding, fonts.
Data types, variables, operators, type coercion, conditionals (if/else/switch), loops (for/while/do-while), break/continue.
Array, String, Number, Boolean objects, event handling (bubbling/capturing), error handling, form validation, scope.
Semantic HTML & accessibility, web security (XSS/CSP/CORS), Web Components, modern CSS selectors, container queries, event loop, promises, performance APIs.
Full HTML/CSS/JS editor with live preview and console. Experiment freely, save your work, and export as HTML.