During the last year and a half, I’ve studied several aspects of statistics and machine learning is one topic which has fascinated me. Hence, in order to get a deeper understanding of machine learning, I’ve decided to write a review of classification methods. I will explain the universal classification rule in chapter 1. In chapters 3-9, I’ll use seven methods to work out a classification problem using two types of algorithms that I will explain in chapter 2. The dataset synthesized by me is illustrated in Figure 1. The dataset and R codes for each chapter are included.