MIDI stands for Musical Instrument Digital Interface. In the context of a drill drum kit, MIDI files are musical files that contain information about the notes, durations, and other musical parameters, allowing you to use them with virtual instruments or hardware synthesizers to create melodies and chord progressions. One-shots, on the other hand, refer to single samples that are designed to be triggered individually. In a drill drum kit, one-shots can include drum hits, vocal samples, or any other sound that can be played independently.