Bootstrap is a free, Open-source and the world's most popular framework for building responsive, mobile-first sites, with jsDelivr frontend toolkit. Bootstrap was developed by Mark Otto and Jacob Thornton at Twitter, in August 2011 on GitHub.
Bootstrap 5 is the latest version with new components, faster stylesheet and more responsiveness. Bootstrap 5 supports all major browsers and platforms except Internet Explorer. If you require Internet Explorer support, please use Bootstrap v4.