One of the widely used research area in todays world is artificial intelligence and one of the scope full area is Machine Learning (ML). This is literature review paper describing ML, the process of machine learning. It is a science making system (computers) to understand from the past behaviour of data or from historic data to behave smartly in every situation like human beings do. Without having the same type o situation a human can behave or can react to the condition smartly. So with the help of machine learning also an effort is been taken to make and act computer smart getting computers to learn and act like humans do, by serving them data and information in the form of observations and real-world communications. This paper also gives the some application areas where ML is already working successfully. https://journalnx.com/journal-article/20150669