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Bootstrap is a free and open-source collection of tools for creating websites and web applications.
It contains HTML- and CSS-based design templates for typography, forms, buttons, navigation and other interface components,
as well as optional JavaScript extensions. It aims to ease the development of dynamic websites and web applications.
Bootstrap is a front end framework, that is, an interface for the user, unlike the server-side code which resides on the “back end” or server.
HTML 5 is a markup language for describing web documents (web pages).
HTML stands for Hyper Text Markup Language
A markup language is a set of markup tags
HTML documents are described by HTML tags
Each HTML tag describes different document content
CSS is a stylesheet language that describes the presentation of an HTML (or XML) document.
Bootstrap CSS:
CSS describes how elements must be rendered on screen, on paper, or in other media.
Global CSS settings, fundamental HTML elements styled and enhanced with extensible classes, and an advanced grid system.
also typography,table,forms,buttons,images,helper classes,responsive utilities,using less,using sass and much more.
Bootstrap Components:
Over a dozen reusable components built to provide iconography, dropdowns, input groups, navigation, alerts,glyhicons,buttons,
navs,navbar,breed crumbs,pagination,jumbotron,page header,thumbnails,list group,panels,wells,responsive embed,media objects,progress bars and much more.
Bootstrap JavaScript
Bring Bootstrap’s components to life with over a dozen custom jQuery plugins. Easily include them all, or one by one.for examples transitions,model,scrollspy,tab,tooltip,popover,collapse,carousel,affix and much more.

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