Using sequencer software, the computer acts like a tape recorder. However, instead of recording the sounds, the sequencer records the MIDI information which tells which notes were used, how they were used, etc. This data can be stored to disk or edited in a variety of ways. For example, tempo can be changed without changing the pitch. Also, passages can instantly be transposed to another key.
Sequencers can also record and play back different parts of a composition in a multi-track manner.
Therefore students can record a basic chord pattern, then listen to it while adding a melody line. Then these two parts can be played while a bass part is added, and so on. When the process is completed, the computer can then print out a complete score. Sequencers are also helpful for professional musicians who are composers. Another use for computers and keyboards for students is in individualized music instruction.