Bootstrap is an open source, sleek, intuitive, and powerful, mobile first front-end framework for faster and easier web development. 

The following are the benefits of using Bootstrap −

• Bootstrap 3, framework consists of Mobile first styles throughout the entire library instead them of in separate files.
• It is supported by all popular browsers.
• With just the knowledge of HTML and CSS, anyone can get started with Bootstrap.
• Bootstrap's responsive CSS adjusts to Desktops, Tablets, and Mobiles.