The fastest note value among the options you provided is the 16th note. Note values can be understood in terms of duration:
- 16th note: Represents 1/4 of a quarter note.
- 8th note: Represents 1/2 of a quarter note.
- Quarter note: Is 1 full beat in 4/4 time.
- Half note: Represents 2 beats in 4/4 time.
Thus, in terms of speed, the 16th note is the quickest.