Learning a Programming language like Java or Python is easy but writing production quality Code is difficult. Coding is as much an art as much the Science behind it. In order to write good code, you need to carefully design your classes, their dependency and how to use that. This is important so that it can survive the constant change throughout his lifetime. If you have been coding for some time then you know that SOLID principles and Design Patterns help you to write better code. This is obvious because they are proven the solution of some common problems software developers face all around the world. But, knowing just the design pattern is not enough you also need to learn using the right design pattern in the right place.