If you want to solve a business problem with your software. You must understand the problem domain first. Next, you should try to break the problem into small-small problems. For each small unit, a problem finds out a solution and write a single function to solve a very small business problem. Hence finally you can solve the entire business problem with a bunch of functions which are called autonomous components. In this section, you will learn how you can write Autonomous Components and What are ES6 Barrels why and how can you use them.