Subject: Styling (Beautify) Website
Bootstrap is a free front-end framework for faster and easier web development. It includes HTML and CSS based design templates for typography, forms, buttons, tables, navigation, modals, image carousels and many other, as well as optional JavaScript plugins.
Bootstrap also gives you the ability to easily create responsive designs, that is; CSS design that adjusts to phones, tablets, and desktops screen or display
How to add Bootstrap to your web page You can easily add Bootstrap framework to your web page without having to download anything, but by including it from CDN (Content Delivery Network) to the HEAD section of your HTML file using the link ref for it's CSS and script src for it's JS.
Contents are wrapped within Containers You will then have your web page contents in the BODY of the HTML file wrapped around the container class of Bootstrap.