What are turnovers in football?

Turnovers occur when the offense accidentally gives the ball to the defense in two ways: fumble and interception.
A fumble occurs when the runner or passer falls to the ground after three seconds of possession, and any player can recover the ball by falling on it or picking it up and running with it.
An interception occurs when the defense catches a ball that was intentionally thrown to a player of the other team.