Acceptance testing is a way to make sure that a piece of software (like a cool game or new app) works the way it's supposed to. Whenever someone creates a new piece of software, it has to be tested to make sure it does the things it's supposed to do and does them correctly. Acceptance testing is one type of testing. It's specifically for checking that the software is meeting the requirements of the person who wants it made, like a company or the customer who requested the software. To do this, the software is tested in a controlled environment, like on a computer or in a special testing lab. That way, everything can be checked and compared to what was asked for before the software goes out to the people who actually need it.