We all know that computers are complex devices, machines made out of an amalgam of electronic parts and componentsBut which computer components are essential for a computer to run? Modern PCs can still function fully without Bluetooth or a floppy disk driveHere is a list of computer components that a computer system cannot do without.

* Motherboard

The motherboard is a very basic unit in any computer systemThis is the computer component to which all other internal computer components are attachedIt links all the other main components of a computer system togetherConsequently, motherboards are sometimes referred to as the "heart" of a computer system.

* CPU

The central processing unit or CPU is the computer component responsible for running programs and applications on the computerWithout a CPU in your computer, you will not be able to do any tasks -- you cannot boot to an operating system, you cannot play music, videos and games, and you cannot do any word processingFor a computer to function, it has to have a CPU.

* RAM

Random Access Memory or RAM is another vital computer componentIt is the storage media where a computer temporarily stores files and information that it can pull at random when running programs and applicationsTogether with the CPU, RAM determines the computer's speedA computer with a large RAM and a mediocre CPU can actually run faster than a computer with a powerful CPU but low RAM.

* HDD

As opposed to the RAM, the hard disk drive or HDD stores computer files and data long-termEven without power, the hard drive still retains the files stored inside itThe hard drive can store important system files like the operating system, program files and other dataIt can also be used to store mp3s and videosIf the computer runs out of RAM, it will temporarily use the hard drive as a virtual memory bank.

* Video Card

A video card allows a computer to display images on the computer monitorIt helps speed up the rendering of images onscreen and contributes to clearer and detailed picturesPC gamers and multimedia software users will find a high-end dedicated graphics card helpful in running graphics-intensive programs smoothly.

* PSU

The power supply unit or PSU supplies all computer components with powerIt converts the high voltages from an AC power outlet to lower voltages that are safe for internal computer componentsWithout a PSU, a computer and its components will not be able to power up.

A computer can also benefit from an optical drive to read and play CDs and DVDs, a network card and router for connecting to the Internet, and peripheral devices such as printers and scannersThe motherboard, CPU, RAM, HDD, video card and PSU are, however, the main components that make up a computer system.