Web 2.0 Study Guide

📖 Core Concepts Web 2.0 – a shift from static “read‑only” pages to interactive, user‑generated, collaborative sites; not a formal version of the Web. User‑generated content (UGC) – text, images, video, audio created by end users and shared on the platform. Folksonomy (Tagging) – free, user‑driven classification that creates emergent organization of information. Rich Web Application – browser‑based software that feels like a desktop app (dynamic UI, real‑time feedback). Web‑Oriented Architecture (WOA) – exposes functionality (feeds, APIs, mashups) so other apps can reuse it. SLATES – six core Web 2.0 functions: Search, Links, Authoring, Tagging, Extending, Sharing. Mashup – combination of data/services from multiple sources via APIs to create a new application. 📌 Must Remember Coined: Darcy DiNucci, 1999; popularized by O’Reilly & Dougherty, 2004. Core features: UGC, rich UX, participation (comments, likes), folksonomy, openness, scalability. Key client‑side tech: Ajax (JavaScript + DOM), JSON/XML, JavaScript frameworks, HTML 5 (replaced Flash). Key server‑side tech: RDBMS, RSS/Atom/JSON feeds, RESTful APIs. SLATES acronym – remember each letter; it maps directly to common platform capabilities. Criticism highlights: buzzword claim, re‑packaged Web 1.0 tech, exploitation of free labor, accessibility trade‑offs. 🔄 Key Processes Ajax request cycle User action → JavaScript creates XMLHttpRequest → Sends async request to server → Server returns JSON/XML → JavaScript updates DOM without page reload. Creating a mashup Identify two or more open APIs → Authenticate (if needed) → Pull data (usually JSON) → Transform/merge data → Present via a Rich Web App UI. Tagging workflow (folksonomy) User uploads content → Enters free‑form tags → System stores tag‑item pairs → Tag cloud generated for navigation and discovery. 🔍 Key Comparisons Web 1.0 vs. Web 2.0 Content: static pages vs. dynamic UGC. User role: consumer vs. participant/author. Interaction: hyperlinks only vs. commenting, liking, sharing. Ajax vs. Traditional full‑page reload Network: single lightweight request vs. whole HTML page. UX: seamless, partial updates vs. visible page refresh. HTML 5 vs. Adobe Flash Standard: native browser support, open standards vs. proprietary plug‑in. Device compatibility: works on mobile & tablets vs. limited mobile support. ⚠️ Common Misunderstandings “Web 2.0 = blogs & wikis.” – the original vision encompassed any participatory, data‑driven service (social networks, video platforms, APIs). “Ajax replaces HTTP.” – Ajax is just a technique that uses HTTP; the underlying protocol stays the same. “All Web 2.0 sites are free.” – many rely on user‑generated content as a revenue source (ads, data licensing). 🧠 Mental Models / Intuition “Platform as Lego bricks.” – Think of each API/feed as a LEGO piece; the rich app is built by snapping pieces together, not by reinventing the whole structure. “Read/write Web = collaborative canvas.” – Visualize the Web as a giant whiteboard where anyone can draw; the more people draw, the richer the picture becomes. 🚩 Exceptions & Edge Cases Performance on low‑end hardware – Ajax‑heavy sites can lag; fallback to server‑rendered pages may be needed. Accessibility – Dynamic content can break screen readers; ARIA attributes and progressive enhancement are essential. Legal licensing – Terms of Service may claim perpetual rights to user content; not all platforms grant users full ownership. 📍 When to Use Which Use Ajax when you need real‑time UI updates without disrupting user flow (e.g., live search, infinite scrolling). Choose HTML 5 video/audio over Flash for cross‑device compatibility and SEO friendliness. Expose an API (REST/JSON) when you want third‑party mashups or mobile apps to consume your data. Adopt SLATES as a checklist when evaluating an enterprise Web 2.0 platform: does it support Search, Links, Authoring, Tagging, Extending, Sharing? 👀 Patterns to Recognize “Like/Share/Comment” triad – appears on most social platforms; signals participation feature. Feed‑driven UI – a list of items refreshed via Ajax (e.g., Twitter timeline, Facebook newsfeed). Tag cloud emergence – when many user tags exist, a visual cloud often appears to aid navigation. 🗂️ Exam Traps Distractor: “Web 2.0 = new HTTP version.” – Wrong; it’s a usage paradigm, not a protocol change. Distractor: “All Web 2.0 sites require Flash.” – Incorrect; HTML 5 replaced Flash for most modern apps. Distractor: “Ajax eliminates the need for servers.” – Misleading; Ajax still communicates with a server for data. Distractor: “SLATES only applies to consumer‑grade sites.” – False; SLATES is used to describe enterprise‑grade platforms as well. --- Use this guide for a rapid, confidence‑boosting review before your exam.