Computer Aided Diagnosis (CAD) is quickly evolving, diverse field of study in medical analysis. Significant efforts have been made in recent years to develop computer-aided diagnostic applications, as failures in medical diagnosing processes can result in medical therapies that are severely deceptive. Machine learning (ML) is important in Computer Aided Diagnostic test. Object such as body-organs cannot be identified correctly after using an easy equation.They also respect the dispassion of the method of decisions making. ML provides a respectable approach to make superior and automated algorithm for the study of high dimension and multi – modal bio medicals data. The relative study of various ML algorithm for the detection of various disease such as heart disease. It calls focus on the collection of algorithms and techniques for ML used for disease detection and decision making processes.