Different Parts of the Computer and Their Function

By David Nield

Every part of a computer has a specific role to play.
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Though computer design has evolved through the years and the underlying technology has become faster and faster, the core components which make up a computer system haven't changed much from the very early days. Each computer, whether desktop or laptop, is made up of the same key parts, with each one given a specific job within the system.

The CPU and RAM

The two components at the heart of every computer are the Central Processing Unit (CPU), which handles most of the computer's calculations, and the Random Access Memory (RAM) modules, which store file data while the computer is switched on (the contents of the RAM memory are lost when the PC is switched off). Generally speaking, a faster CPU means more calculations in a shorter period of time, and therefore a faster machine. More RAM means more files and programs can be open and running at the same time without the machine grinding to a halt. The same CPU/RAM core specification combination can be seen across computers, tablets, mobile phones and other devices.

Motherboard and Ports

The motherboard acts as the backbone to the system, connecting components such as the CPU and RAM modules together and managing communications between them. The type of motherboard also determines the number and type of available ports, such as a HDMI output or a USB input. The motherboard is responsible for handling input and output signals, as well as transferring data to and from the installed disk drives. The motherboard and the system itself are powered by a Power Supply Unit (PSU) that draws power from the mains or (in the case of a laptop) the installed battery.

Hard Disks and Optical Drives

Hard disk drives store all of a computer's data, including personal files, applications and the operating system. Hard disks are sometimes used as overflow for temporary data when the RAM modules are full, but they operate much more slowly. Many systems now make use of the faster Solid State Drives (SSDs) rather than traditional hard disks, but the principles are the same — the drive is used to store all of the data held by the computer. Optical disc drives are also installed on some systems to read and write CDs, DVDs and Blu-ray discs.

Other Components

On smaller systems or laptop computers, the graphics and audio capabilities of a computer are integrated into the motherboard. Larger desktop PCs often have a dedicated graphics card (or two) and a dedicated audio card to provide more processing power and take some of the strain off the main CPU and RAM, leading to better performance. Other expansion cards available for desktop PCs include TV tuner cards (for receiving and recording TV signals) and network cards for connecting to a local network (though this functionality is now usually included on the motherboard).