What is the difference between stack and heap memory in JavaScript?
Stack stores primitives and references (fast, LIFO, per-function frames). Heap stores objects, arrays, and functions (unstructured, managed by the GC). Variables hold references to heap objects.
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More FAQs in Memory Management in JavaScript: A Complete Guide
Automatically. The engine allocates memory (stack for primitives, heap for objects), you use it, and the garbage collector frees unreachable memory. You do not manually allocate or free memory like in C/C++.
Accidental globals (x = 5 without let), forgotten timers (setInterval never cleared), event listeners on detached DOM elements, closures keeping large objects alive, unbounded caches, and detached DOM references.
Chrome DevTools Memory tab (take heap snapshots, compare). Performance tab (record memory over time, look for growth). performance.memory.usedJSHeapSize (Chrome only). process.memoryUsage() in Node.js.
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