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HTML: Markup language
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Date & time formats
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CSS: Styling language
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Centering an element
JavaScript: Scripting language
Standard built-in objects
Expressions & operators
Statements & declarations
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Control flow & error handing
Loops and iteration
Working with objects
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Web APIs: Programming interfaces
Service worker API
Using the Web animation API
Using the Fetch API
Working with the History API
Using the Web speech API
All web technology
Progressive web apps
Learn web development
Getting started modules
Structuring content with HTML module
CSS styling basics module
Dynamic scripting with JavaScript module
Border-image generator
Border-radius generator
Box-shadow generator
Color format converter
Strict inequality (!==)
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This page was last modified on Jul 8, 2025 by MDN contributors.
Expressions and operators
Numbers and strings
Representing dates & times
Regular expressions
Indexed collections
JavaScript typed arrays
Iterators and generators
Resource management
Internationalization
JavaScript modules
JavaScript data structures
Equality comparisons and sameness
Enumerability and ownership of properties
Inheritance and the prototype chain