As a developer, while doing coding task, there is a probability that we make some mistakes accidentally. Sometimes, the compiler catches the mistakes and warns us to correct it. But when we make a mistake and compiler didn't catch it, we may face an issue after running the program. That's why we should have some elementary knowledge of Java Coding Best Practices and Standards in order to avoid them. These Java Coding Best Practices and Standards are not only useful in writing a successful program, but also in improving the performance of the application in the long term as a whole. Based on the Code Review, we are going to mention a synopsis of the common mistakes that a Programmer commits.