JavaScript Concepts
Fundamental JavaScript concepts: sync vs async, primitives vs objects, type systems, module systems, SPAs, and JavaScript engines.

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This unit covers fundamental JavaScript concepts and theory that every developer should understand.

We’ll explore the differences between synchronous and asynchronous code, how primitive types differ from objects, what it means for JavaScript to be loosely typed, how module systems work, what Single Page Applications are, and how JavaScript engines like V8 execute your code.

These concepts form the foundation for understanding how JavaScript works under the hood.

Lessons in this unit:

0: ▶︎ Introduction
1: Synchronous vs Asynchronous
2: Primitive types vs Objects
3: Loosely vs Strongly typed
4: CommonJS module system
5: What is a Single Page Application?
6: V8 and JavaScript engines
7: JSONP: The predecessor to CORS
8: Finite State Machines