Bootstrap is an open source toolkit for developing with HTML, CSS, and JS. Quickly prototype your ideas or build your entire app with our Sass variables and mixins, responsive grid system, extensive prebuilt components, and powerful plugins built on jQuery.

1. Introduction to bootstrap

2. outline
 What is bootstrap ?
 What is a web framework ?
 History
 Advantages
 Some disadvantages
 Getting started
 Grid system

3. What is bootstrap ?
 Bootstrap is a web design framework that makes it easy for you to build responsive
websites quickly and effectively. Web developers at Twitter created Bootstrap to help them
build their website.

4. What is a web framework ?
 A web framework is a tool that programmers and web developers can use to
simplify a complex system, such as a website or web application. A web
framework is a development framework for websites, and several are available
for designers and developers to use,

5. History
 Developed by Mark Otto and Jacob Thornton at Twitter
 Released as an open source product in august 2011 on github
 In june 2014 bootstrap was the No.1 project on github

6. advantages
 Easy to use
 Browser compatibility
 Responsive feature
 Mobile First approach
 Several JavaScript plugins using the jQuery
 Great grid system

7. Some disadvantages
 Styles are verbose and can lead to lots of HTML output that's not perfectly
semantic.
 JavaScript is tied to jQuery (it's by the far the most common JavaScript library
though and the plugins can just as easily be left unused).
 Can require lots of overriding styles or rewriting their files if you have lots of
customizations or want to deviate from Bootstrap structure.
 Websites can start to look the same if you don't customize the styles and colors
much.

8. Getting started
 Download
 Bootstrap CDN

9. Grid system
 Bootstrap includes a powerful mobile-first flexbox grid system for building layouts
of all shapes and sizes. It’s based on a 12 column layout and has multiple tiers

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