Android 17 is the twin brother of Android 18 and Dr. Gero's seventeenth android creation, a cyborg due to being a human at one point, and one of his first human subjects, designed to serve Gero's vendetta against Goku, who overthrew the Red Ribbon Army as a child. Despite his interests not initially deviating from this expectation, Android 17 takes it upon himself to kill Dr. Gero, who is uncooperative with Android 18's curiosity in activating Android 16 and deemed inferior by 17.
Dragon Ball Super
Android 17 makes a return a decade later in Dragon Ball Super, working as a national park ranger preserving wildlife from poachers. He is married and has a child, with two more children being adopted. He is asked by Goku to join Team Universe 7 in the Tournament of Power in the Universe Survival Saga.