Acoustic signals are vibrations in air produced by the movement of non-living objects in our daily life. These can be due to vehicles, turbines, machines and so many different objects. Classification can be done using Machine Learning techniques where we train the machine with some training data whose labels are known and get the class or label of test data whose class is not known. There are many pre-defined classification algorithms like KNN, SVM, RANDOM FORESTS, etc. In this project we are using KNN, Decision tree, NAÏVE BAYES for classification purpose. As Acoustic signal is a vast topic, here our application of acoustic signals is in vehicle classification. By using microphone we collect large amount of train data and classify vehicles depending on that data. We discuss further in the introduction part.