Lab

How the Event Loop Works

medium
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Step Explanation

Understand what is happening first

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Execution Visualizer

Watch memory, stack, queues, and output

Execution Visualizer

live
JavaScript starts executing the script from top to bottom. console.log('Start') is a synchronous operation — it runs immediately on the call stack.

Call Stack

2 frames
TOP ↑
console.log('Start')
frame 1
main()
frame 0
↓ BOTTOM
Global Context

Memory

0 variables

No variables in memory

Console Output
01Start
varfnobjarrclosure

Code Preview

Active line 1

Code

line 1
JavaScript
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