Automation testing is the process of automatically testing software for bugs. Automated software tools are capable of executing scripted tests on the tested software application, reporting outcomes and comparing results with earlier test runs. The great advantage of automation testing is that it can be carried out repeatedly and at any time. Test automation can reduce the cost of testing. It can follow the test steps more quickly than a manual tester and it can perform some additional tests which are difficult to perform manually, which results in a better coverage.
It’s possible that the work effort of automating the test cases is greater than performing the tests manually. Therefore, manual testing must be carried out prior to start automating test cases to check the feasibility of automation testing.