OEM
Original Equipment Manufacturer
Operating System
Software program that facilitates communication between the computer and its user
Outside Diameter
Largest radius track on a platter
Parity
a data error detection method, that ensures that the number of binary digits in a bit is always odd, so that accurate transmission of data can be checked by counting the number of bits for an odd parity
Partitioning
division of the area on the platter and allocating sections each of which becomes a logical device, so that the File Allocation Table (FAT) can deal with when in use
Parallel Port
PC peripherals are commonly connected to a PC via the parallel port
PCB
Printed Circuit Board, board that has the HDD chips attached to it
PCI
Peripheral Component Interconnect
Periphera
components usually attached to a computer systems CPU by controllers and cables
Plated Media
platters whose surface is plated with metallic alloy , allowing the disc to store more data than on iron-oxide plated discs
Platter
the magnetic disc that is part of a disk drive, the part of the HDD on which the data is stored
POH
Power on Hours
PnP
Plug and Play, the ability for users to plug in new devices into their existing system and immediately be able to use it, as a result of a group of leading hardware manufacturers (initiated by Microsoft), who have configured their hardware so that it automatically identified and configures peripheral devices
PRML
Partial-response maximum likelihood. Data is stored on hard drives as a tiny area of magnetism for each bit. As more and more data is squeezed on a disk, the magnetic areas become closer and closer and may affect one another. PMRL is a set of steps applied to data read from the disk. It removes probable errors and produces valid data from the tightly packed bits. PMRL allows an increase of up toe 30 % in the density of data on the disk
