Akai iMPC - Manual (Page 5)

Data wheel
The data wheel is a continuous/jog wheel that scrolls though the sequences.
Turn the wheel clockwise to advance the Sequence, counter-clockwise to
move to a previous Sequence. Try this during playback to queue up different
sequences in succession. iMPC will wait to start playing a new sequence
until the previous sequence has finished. Use this to string together
Sequences in order for a real-time performance.
Time Correct
Time Correct will automatically fix your recorded patterns to a set timing