An arrow curving back to the left, reversing the last action.
An arrow curving anticlockwise reverses the most recent action. Its mirror redoes what was undone, and the pair is one of the few interface conventions that is genuinely universal.
Reverses the most recent action, usually one step at a time through a history of changes.
Contexts: Software
An arc sweeping from right to left with an arrowhead at its left end, curving back on itself like a road doubling round.
Both are built from arrows, and both are used in software contexts.