First of all let us see what is a framework

A framework is a pre-designed software or toolset that provides a structured approach to developing applications. It offers a set of reusable components, libraries, and utilities that help developers build applications more efficiently by providing ready-made solutions to common problems. Frameworks often follow certain conventions and design patterns, allowing developers to focus on the specific functionality of their application rather than the underlying infrastructure.

Bootstrap is the most popular CSS Framework for developing responsive and mobile-first websites.

With Bootstrap you can,

• easily create responsive websites.
• quickly create multi-column layout with pre-defined classes.
• quickly create different types of form layouts.
• quickly create different variation of navigation bars.
• easily create components like accordions, modals etc. without writing any JS code.
• we can quickly create different types of alert boxes.
• we can easily create dynamic tabs to manage large amount of content.
• we can easily create tooltips and popovers to show hint text.

Advantages of using Bootstrap

• Save lots of time - We can save time and effort using the Bootstrap predefined design templates and classes.
• Responsive features - Using Bootstrap we can easily create responsive websites that appear more appropriately on different devices such as mobile devices with different screen resolutions.
• Consistent design - All Bootstrap components share the same design templates and styles through a central library, so the design and layout of our web pages will be consistent.