According to AJ

What is test automation? Wikipedia says: 'In  software testing ,  test automation  is the use of  software  separate from the software being tested to control the execution of tests and the comparison of actual outcomes with predicted outcomes.' Therefore, we automate the way how we - the user or just a consumer of an API - uses the application. There are two big groups: GUI testing When we do automated testing in this group, then we actually record an ordered set of user actions, then we run them against the softer under test, and then we check the result against the expected result. API driven testing When we do automated testing in this group, then we have no GUI. We have only an interface that can be accessed by our automated tests, then we just pass many kinds of parameters into it and verify the results against the expected. Example In our example, we have a SchoolManagerGUI, where the User can change the type of the IKitchenService with a few clicks on the UI. Note that

The short answer is, the bricks in the wall!  😊 Let's check it via an example Imagine, we are participating in a bigger project with multiple developers for a long time. We have just started the project from zero without any common agreements on how to build up the project. There are no best practices on how to develop the project, we all just apply the changes ad-hoc, as it is. The goal is to finish the project fast! ...time passes by... We have already spent quite a lot of time on the project next to the other developers, and we are starting to think it is getting harder and more complicated to implement new features in the app -> it is challenging to figure out which code to modify, what is safe to be extended. Things get even more complicated when requirements change at the very last minute, and the project's code is not dynamic enough to handle these unexpected changes in an acceptable time. And we have these many new annoying, unexpected bugs! ..and this list could go