Brute-force attack is simply to continuously attempt to discover your password by combining all possible passwords it can guess. That said, human can guess a password by trying to brainstorm all possibilities such as birthday, girlfriend name, a memorable location or even a combination of birthday and full name. The problem is that our brain cannot come up with a million of guesses and type the guessed password into the login form. Unless you are so-called a time-billionaire. With a tool, it can guess and automatically fill into the login form. Whenever it receives a message like “Successful login” it will stop the guessing process.