JavaScript in Depth
JS: Filename Extension
By Xah Lee. Date:
2025-05-21
. Last updated:
2025-11-18
.
.js
normal JavaScript filename extension
.mjs
sometimes used for JavaScript modules.
JS: Module
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JS
Basics
Filename Extension
Run JavaScript
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Assignment
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Test Equality
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Array basics
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Object and Inheritance
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Class
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for-of Loop
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Import
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Promise
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Try Catch Throw
Style Guide
Semicolon
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Timing JS Code
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