Raspberry Pi Documentation - Raspberry Pi hardwareA powerful feature of the Raspberry Pi is the row of GPIO (general-purpose input/output) pins along the top edge of the board. A 40-pin GPIO header is found on all current Raspberry Pi boards although it is unpopulated on Raspberry Pi Zero, Raspberry Pi Zero W, and Raspberry Pi Zero 2 W. The GPIO headers on all boards have a 0.1-inch (2.54 mm) pin pitch. Any of the GPIO pins can be designated in s
