Code

console.log("a");

setTimeout(() =&gt; console.log("b"), 1);
setTimeout(() =&gt; console.log("c"), 10);
setTimeout(() =&gt; console.log("d"), 0);

console.log("e");

Execution Flow

Synchronous phase
- "a" prints immediately.
- setTimeout calls schedule their callbacks in the timer queue.
- "e" prints immediately.
  
  👉 Output so far:
```
a
e
```
Timers phase
- Both b (1ms) and d (0ms) are eligible on the next tick.
- Timers are not guaranteed to run at exact ms — they just run after the minimum delay and when the call stack is clear.
- Among timers ready at the same time, execution order follows registration order.
- So: b runs, then d.
Later timer
- After ~10ms, c runs.

Final Output

a
e
b
d
c

Key Takeaways (interview points)

setTimeout(fn, 0) does not run immediately; it queues fn for the next event-loop tick.
Timers with very small delays (0ms, 1ms, etc.) usually fire together, in the order they were scheduled.
Event loop ensures synchronous code finishes first, then queued tasks run.

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