Brute force cracker is a tool used to illegally obtain passwords. There are several problems using tools like this. First it's illegal. Second the software runs through every possible combination until it cracks the password. The problem here it is time consuming, we're talking days. CPU power is an issue along with the fact that almost all sites have set up safety features that prevent the
. wrong password from being entered so many time. This number is usually 5 which stops the theory of running millions of combinations in its tracks. It just is not worth the time, effort or the jail time if you are caught.