This document discusses different types of ammeters. It begins with an introduction on what an ammeter is and provides a brief history on their development. It then outlines the main types of ammeters which include moving-coil ammeters, electrodynamic ammeters, moving-iron ammeters, hot-wire ammeters, digital ammeters, and integrating ammeters. Each type is then described in 1-2 sentences on their basic operating mechanism.