Written guides

JavaScript Execution Guides

Deep, spec-grounded explanations of how JavaScript actually runs — each guide pairs a precise mental model with runnable traces you can open in the visualizer.

  1. JavaScript runtime guide

    How JavaScript Executes Code: From Global Code to Function Return

    A precise mental model for JavaScript execution contexts, function calls, lexical environments, and the call stack.

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  2. JavaScript declarations guide

    JavaScript Hoisting: Declarations, Initialization, and the Temporal Dead Zone

    A practical explanation of why var, let, const, and function declarations behave differently before their source lines run.

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  3. JavaScript scope guide

    How the JavaScript Scope Chain Works

    Understand lexical scope, identifier lookup, shadowing, and closures through small JavaScript traces you can run.

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