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LetsGit.IT/Categories/JavaScript
JavaScripthard

What is the event loop and how do microtasks differ from macrotasks?

Tags
#event-loop#async
Back to categoryPractice quiz

Answer

The event loop processes the call stack and task queues. Microtasks (e.g., Promise callbacks) run before the next macrotask (e.g., setTimeout).

Advanced answer

Deep dive

Expanding on the short answer — what usually matters in practice:

  • Context (tags): event-loop, async
  • Explain the "why", not just the "what" (intuition + consequences).
  • Trade-offs: what you gain/lose (time, memory, complexity, risk).
  • Edge cases: empty inputs, large inputs, invalid inputs, concurrency.

Examples

A tiny example (an explanation template):

// Example: discuss trade-offs for "what-is-the-event-loop-and-how-do-microtasks-dif"
function explain() {
  // Start from the core idea:
  // The event loop processes the call stack and task queues. Microtasks (e.g., Promise callbac
}

Common pitfalls

  • Too generic: no concrete trade-offs or examples.
  • Mixing average-case and worst-case (e.g., complexity).
  • Ignoring constraints: memory, concurrency, network/disk costs.

Interview follow-ups

  • When would you choose an alternative and why?
  • What production issues show up and how do you diagnose them?
  • How would you test edge cases?

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