Bootstrap
The most popular HTML, CSS, and JS library in the world.

Bootstrap is an open-source frontend toolkit providing a responsive grid system, prebuilt UI components, and JavaScript plugins for building websites and web applications. It supports deep customization through Sass variables and a utility API, allowing developers to tailor styles without rewriting core rules. The library is available via CDN, npm, RubyGems, Composer, and Meteor.
Developers include Bootstrap via CDN or package manager and use its prebuilt CSS classes, Sass variables, and JavaScript plugins to rapidly build and customize responsive UI components.
web developers and frontend engineers
Background.
- Status
- launched
- Business model
- open-source
Similar projects.
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