This Plug has a  Multatude of uses for Audio, Video and Computer Applications.
The Audio application generally use two common wiring standards.

Some Example of a Wiring Configuration 

From Apple (CTIA) & Computer Headsets
Tip (Left), Ring1 (Right), Ring 2 (Ground), Sleeve (Mic)
From Nokia / Samsung (OMTP) 
Tip (Left), Ring1 (Right), Ring 2 (Mic), Sleeve (Ground)

AV – Cables is wired for Audio Left + Right and Video
Camcorder AV
Tip (Left), Ring1 (Viideo), Ring 2 (Ground), Sleeve (Right)
Apple AV
Tip (Left), Ring1 (Right), Ring 2 (Ground), Sleeve (Video)

For Computer to USB (Android / IOS Devices)
Tip (Power) +5V),
Ring1 (Data D-),
Ring 2 (Data D+),
Sleeve (Ground 0V)