Arrange, Act and Assert.Arrange is how we get the data or how we declare it? For example, fetching data from a database but when we are testing we are going to expect some mockup so, Arrange would mean creating that mockup?Act is to perform the action that we are testing, for example if the method Add_Two_Numbers add 2 numbers together.Assert is based on the value returned from the Act, we compare the actual value and the expected value to see if the test is right or wrong?