Bootstrap is a responsive web framework, meaning it is designed to adapt layout and design for screen sizes large and small, such as mobile devices, tablets and desktop computers, all in a single code base.
One of the fundamental concepts of Bootstrap is the grid framework. By applying classes to HTML elements, it is possible to create intricate layouts using a basic grid of twelve columns. For example, a four column layout might adapt to two columns on tablet devices and one column on mobile devices. The grid uses
media queries, a CSS method for targeting specific screen sizes, to achieve this.
Bootstrap performs particularly well if: