Bootstrap is a free and open-source tool collection for creating responsive websites and web applications. It is the most popular HTML, CSS, and JavaScript framework for developing responsive, mobile-first websites. Nowadays, the websites are perfect for all browsers (IE, Firefox, and Chrome) and for all sizes of screens (Desktop, Tablets, Phablets, and Phones). All thanks to Bootstrap developers – Mark Otto and Jacob Thornton of Twitter, though it was later declared to be an open-source project.
By building with Bootstrap, you can check that last item off your list. Bootstrap is an open-source framework for quickly building responsive websites and mobile-first web projects. Because it offers a collection of reusable code, you won't have to build a site from scratch.
Bootstrap is available in two variants ‒ precompiled and based on a source code version. Experienced developers prefer the latter since it lets them customize the styles to suit their projects.
You don't need to be proficient at HTML and CSS to use Bootstrap, although it's a plus if you're a backend developer and need to do some UI changes. Bootstrap comes with components you can easily use for your web page, including navigation bars, dropdowns, progress bars, and thumbnails.
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