Web Development Advanced

Lesson Promise

By the end of this lesson, you will understand the tradeoffs between WebSockets, SSE, and polling; how to choose between SPA and MPA; how the browser event loop works; and how caching + security patterns keep web apps fast and safe.

Narration Draft

"The hardest problems in web development aren't about syntax — they're about architecture. WebSockets give you real-time bidirectional communication, but they're hard to load balance. SPAs feel fast but hurt SEO. The browser's event loop lets you do thousands of things at once, but only if you understand how it schedules work. And caching and security don't happen by accident — they require deliberate design."

Visual Sequence

1. Scene 1 — WebSocket vs SSE vs Polling comparison matrix
2. Scene 2 — SPA vs MPA rendering triangle (fast / SEO / interactive)
3. Scene 3 — Browser event loop trace (Trace: trace-event-loops-and-async)
4. Scene 4 — Caching and routing flow (Diagram: flow-caching-and-routing)

Companion Material

• Article: WebSockets vs SSE vs Polling
• Article: SPA vs MPA
• Article: State Management
• Article: Retries and Backpressure
• Article: Security Follows Data and Authority
• Trace: Password Login Verification
• Diagram: Caching and Routing
• Learning Path: Web Development Advanced