Pickup Arm and Cartridge

Here is a pickup arm. The cartridge is the small box mounted at the end of the arm furthest from the pivot:

It normally has four wires attached at the back. The stylus ("needle") is the tiny diamond mounted on the thin tube coming out of the bottom of the cartridge:

Some turntables have an arm and cartridge assembly where the cartridge plugs into the end of the arm without the connecting wires being visible. (I'm afraid I don't have a picture of this).