Introduction to the Web & HTML
Explore the origin story of the World Wide Web, the global networking machinery connecting clients and servers, browser rendering pipelines, and author your very first valid HTML5 page.
🌐 Chapter Overview & Prerequisites
Welcome to the foundation of all web development. Before writing complex applications, you must understand the medium in which your code executes. In this chapter, you will transition from viewing web pages as visual screens to understanding them as distributed hypermedia documents transmitted across network protocols, decoded into in-memory object trees (DOM), and rasterized into pixels by browser engines.
Chapter Lessons
-
1.1
What is the World Wide Web?
Origins at CERN with Tim Berners-Lee (1989), the critical difference between the Internet and the Web, hypermedia concepts, and distributed architecture.
-
1.2
How the Internet Works — Clients & Servers
DNS resolution hierarchies, TCP 3-way handshakes, HTTP request/response transactions, status code categories (200, 301, 404, 500), and MIME types.
-
1.3
What is HTML? — History & Evolution
The definition of HyperText Markup Language, roots in ISO SGML, markup versus programming languages, and the foundational principle of separating structure from presentation.
-
1.4
HTML Versions — From HTML 1.0 to HTML5
Historical progression from HTML 2.0 to 4.01, the strict XML failure of XHTML, the browser vendor rebellion, and the modern WHATWG Living Standard.
-
1.5
How Browsers Render HTML
The Critical Rendering Path (CRP): Bytes → Tokens → Nodes → DOM Tree → CSSOM → Render Tree → Layout (Reflow) → Paint → GPU Compositing.
-
1.6
The Role of HTML in Web Development (HTML, CSS, JS Triad)
Structure (HTML) vs Presentation (CSS) vs Behavior (JavaScript), progressive enhancement philosophy, and how modern reactive frameworks compile into raw DOM elements.
-
1.7
Understanding URLs, URIs, and URNs
RFC 3986 URI grammar, complete anatomy breakdown (scheme, userinfo, host, port, path, query string, hash fragment), and resolving absolute vs relative paths.
-
1.8
HTTP & HTTPS Protocols Overview
HTTP request methods (GET, POST, PUT, DELETE), response headers, protocol evolution from HTTP/1.1 to HTTP/2 multiplexing and HTTP/3 QUIC, plus TLS/SSL cryptographic handshakes.
-
1.9
W3C & WHATWG — Standards Bodies
The history of web governance, the WHATWG browser vendor revolt, the 2019 unification agreement, how to read official specifications, and checking browser support matrices on CanIUse.
-
1.10
Your First HTML Page — Hello World
Authoring a 100% standards-compliant HTML5 document from scratch: <!DOCTYPE html>, <html>, <head>, <meta charset>, <title>, and <body> with live code execution.