Bootstrap

Bootstrap is the most popular HTML, CSS, and JS framework for developing responsive, mobile-first projects on the web and you can access it at http://getbootstrap.com/ .

Bootstrap has many features that meet the various needs of a web application. It has different CSS classes for each of the HTML elements so that you can use it without touching any CSS code. However, if you wish to override it, you can do so.

Let us look at each of the features of Bootstrap in brief.

Bootstrap Grid system

The grid system in Bootstrap helps you to create a responsive layout for your application. This feature makes your application look great in all devices of different shapes including mobile devices.

Bootstrap provides a fluid grid system, which scales up to twelve columns as the device or viewport size increases. You can think of grid system as being like columns in an Excel sheet (like the one in the following screenshot):

We can combine multiple columns to create a wider column. In the second...