The guitar and the bass peripherals both work on the same controller. Similar in design to the Guitar Hero controller, the Rock Band guitar/bass looks more like the real thing since the fret buttons are camouflaged with the color-coding along the side of the neck, rather than the top.
As with the other hardware, operating the guitar/bass is all about timing. The fret buttons select the note, and the strum bar executes the timing. The lever inside of the strum bar sets off an electrical chain reaction that communicates to the software the note you just played. For more detailed information about the guitar controller, read How Guitar Hero Works.
The Rock Band guitar also has a second set of fret buttons near the body. These activate during the solo sections of the songs when rockers can wail to their hearts' content. You can also use the whammy bar to add vibrato to sustained notes. Spicing up the familiar Rock Band controller, you also have a pick-up switch at your disposal that can make five different sound effects during solos and overdrive, which you'll learn about later.
Music data for each of the songs -- broken out into mic, drums, bass and guitar -- are stored as waveform files [source: Yoshitomi et al.]. Waveforms store the music as disparate sections, which is how the game can judge when you've royally missed or hit a note. Depending on the mode and instruments you select to play, the software will pull the corresponding waveform files to allow you to either play solo or with other people.
On the next page, we'll put our instruments into action.