Humbucker

A humbucking pickup (also known as humbucker, or double coil) is a type of guitar pickup. They uses two wire coils to cancel out the noisy interference picked up by coil pickups. 
Humbuckers are one of the two main types of guitar pickup, the other being single coil.
In any magnetic pickup, a vibrating guitar string, magnetized by a fixed magnet within the pickup, induces an alternating voltage across its coil.