In HTML and CSS, Bootstrap is a popular open-source front-end framework that provides a set of pre-built design templates and components for creating responsive, mobile-first web pages and applications. It includes CSS stylesheets and JavaScript files that can be added to a web page to implement a variety of features and functionality, such as responsive layout, navigation menus, forms, tables, buttons, and more.
Bootstrap is designed to simplify the process of web development by providing a standardized set of design elements that can be easily customized and combined to create a professional-looking and functional website. The framework uses a 12-column grid system for layout, which allows developers to create flexible and responsive designs that can adapt to different screen sizes and devices.
Bootstrap is compatible with most modern web browsers and can be used with popular web development tools such as Visual Studio Code, Atom, and Sublime Text. It is widely used by developers and designers to create responsive and mobile-friendly websites and applications quickly and efficiently.