How Do You Play Guitar Hero?

Where I live, when it's on sale, it's around $100. There are preprogrammed songs in it, and it isn't just 3 songs, you attach all the stuff to the game system, and it pretty much guides you through all the rest of it.
You have to know what notes you are going to use in the song, play along with the scroll that rolls upward to the top of the screen, and it will tell you if you are hitting the right cords, or missing out altogether.
At the time, my son was 23, and he asked me to watch him do this. I laughed when he missed the last cord(chord) on the song he was playing. But, he does play the bass, and the acoustic rather well.  Ever heard of Breaking Day, the band? My son was bass player for them. But it is a fun game to get into I guess, if you really like to play the guitar. Hope this helps.