The central processing unit (CPU) is the portion of a computer system that carries out the instructions of a computer program, and is the primary element carrying out the computer's functions. The central processing unit carries out each instruction of the program in sequence, to perform the basic arithmetical, logical, and input/output operations of the system. The form, design and implementation of CPUs have changed dramatically since the earliest examples, but their fundamental operation remains much the same.
Motherboard
In personal computers, a motherboard is the central printed circuit board (PCB) in many modern computers and holds many of the crucial components of the system, while providing connectors for other peripherals. The motherboard is sometimes alternatively known as the main board, system board, or, on Apple computers, the logic board. It is also sometimes casually shortened to mobo.
RAM
Random-access memory (RAM) is a form of computer data storage. Today, it takes the form of integrated circuits that allow stored data to be accessed in any order (that is, at random). "Random" refers to the idea that any piece of data can be returned in a constant time, regardless of its physical location and whether it is related to the previous piece of data.
PSU
A modern computer power supply is a switch with on and off supply designed to convert 110-240 V AC power from the mains supply, to several output both positive (and historically negative) DC voltages in the range + 12V,-12V,+5V,+5VBs and +3.3V. The first generation of computers power supplies were linear devices, but as cost became a driving factor, and weight became important, switched mode supplies are almost universal.
GPU
A graphics processing unit or GPU (also occasionally called visual processing unit or VPU) is a specialized microprocessor that offloads and accelerates graphics rendering from the central (micro-)processor. It is used in embedded systems, mobile phones, personal computers, workstations, and game consoles. Modern GPUs are very efficient at manipulating computer graphics, and their highly parallel structure makes them more effective than general-purpose CPUs for a range of complex algorithms. In a personal computer, a GPU can be present on a video card, or it can be on the motherboard, or as in certain Core Intel CPUs, on a CPU die. More than 90% of new desktop and notebook computers have integrated GPUs, which are usually far less powerful than those on a dedicated video card.
HDD
A hard disk drive (HDD) is a non-volatile, random access device for digital data. It features rotating rigid platters on a motor-driven spindle within a protective enclosure. Data is magnetically read from and written to the platter by read/write heads that float on a film of air above the platters.
OS
An operating system (OS) is software, consisting of programs and data, that runs on computers and manages computer hardware resources and provides common services for efficient execution of various application software.
Next we'll start looking at specific hardware parts.
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