Because of this, having a generic serial out there doesn't always work, so some hackers have made key generators, which allow you to enter a company or personal name, and it will spit out the serial number that will work. In that case, many times they crack a program. Cracking a program involves running the program through a debugger, and removing the section of code where the program checks for the registration info, or checks on what day of the trial you are at. By removing this section, you get a free no-registration version or a demo with no expiration day, respectively. With games, new difficulties are encountered.
Games have the luxury of requiring the game CD, which makes using a mere serial number difficult.
Probably the most humorous thing to see pirated is the full length movie. No one would want it if they could rent it at the movie store, so it requires that someone go to the movies, videotape the movie, come home and upload the movie in a format others can view. This is, to the best of my knowledge, pushing one of the longest articles I have ever written. I could be completely wrong, but I'm too lazy to find all of my other articles and check. Getting past the protection on programs is only the first step.