PowerPC, Performance Optimization With Enhanced RISC, is a RISC microprocessor developed by an Apple-IBM-Motorola alliance in 1991.
IBM and Apple PowerPC based workstations and server systems, such as IBM enterprise server - Apple's iMac, iBook, Mac mini, PowerBook and, older PowerMacs with a G4, G3 or even older PowerPC CPU, as well as Motorola embedded systems - including Compact PCI boards.
Used by quite a lot people in the T2 community and thus usually in a very good shape. Used in high performance and carrier grade embedded appliances.