What is Bootstrap
Bootstrap is a free and open-source framework for creating websites and web applications. It's the most popular HTML, CSS, and JS framework for developing responsive, mobile first projects on the web.
About Bootstrap 4
Bootstrap 4 involves a major overhaul of Bootstrap with some big changes to the way it functions when compared to Bootstrap 3. There have been a lot of changes to most components, including tables, forms, grids, dropdowns, navbars, and more.
Bootstrap 4 alpha was released on 19 August 2015. After two years in various alpha releases, Bootstrap 4 progressed to beta release in August 2017, then to beta 2 in October 2017, and then finally to the full V4 release in January 2018.
Advantages of BootstrapOne of the main benefits of development frameworks like Bootstrap is that they can help speed up development times, while maintaining quality and consistency across the site. You no longer need to re-design every element. And you don't need to spend hours trying to get everything looking and working right across browsers, platforms, and devices. By using Bootstrap, all (most) of the hard work is done for you.