I like to use DNA sequencing, it's a reletively new concept but it is extremely accurate, no latency anomalies or Midi cable issues over 5 metres. You should look into it, the results can be quite breathtaking.
* RealTime Recorded
* Step
* Pattern (using patterns created using RealTime or Step or both)
Drum machines use pattern sequencing. First you tap in some beats to make a pattern in realtime; or, you step sequence a pattern. After that you string together your patterns to make a song.
analog sequencing is voltage based so the transients are buttery smooth and tuning is not always fixed. it is similar to a step sequencer in use. Here is a good example