Components Of Computer System And How Computer Computer Science Essay

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This part of the assignment investigates the components of computer system and how computer system works. This literature survey will be based upon computer system; a computer system needs different principles and requirements such as inputs and outputs to run the system. Some are the computer devices include monitor, keyboard, mouse and many others.

1. Processer (CPU):

Computer processer is also known as CPU the brain of computer, which stands for central processing units. The CPU is the main component of computer; this main component runs the basic instruction in a computer and executes all the commands from the computer output (hardware) and (input) software the CPU usually used in personal computers the central processing unit saves all the instruction that it needs to drive from program memory these instruction covers more than millions of instructions each instruction is stocked at a detailed address. Every CPU includes PC (program counter) which keeps track of CPU's location in the programme. Computer can take any code written in any language because the particular language breaks the code down into assembly language. This assembly language coverts language into binary code, so the CPU can operate to implement the instructions it is given. CPU can perform many things such as calculations it can calculate large and complex mathematic data in seconds using Arithmetic Logic Unit (ALU), can deliver data from one place to another place and can use many different types of addresses in a program based and results made by the central processing unit. Each time the user enters any information trough the CPU output (keyboard) the CPU produces it with some sort of output. what is a cpu

2. Memory:

A computer memory is a luggage compartment system where information can be stored, entered and retrieved. Computer term memory classify data storage this term memory comes in the format of chips, many computers use virtual memory which increase physical memory into a hard drive. Every computer has physical memory usually referred to the main memory or the RAM.

2.1 Primary Memory:

Primary memory or main memory of a computer system which directly contacts to the Central Process Unit (CPU), primary memory holds all the instruction and information accessed and used by the CPU. It is the volatile memory which loses access when the user switches off the system and cannot be recovered.


The Random Access Memory is one the computer memory, which supplies space for computer to convert and mark data to be accessed by the central processing unit. Every computer has RAM memory, increasing RAM of your computer means reducing the number of times your CPU read data from the hard drive. Computer RAM stores the data temporally, stored data sties inside the RAM as long as your PC is running, if you turn off the PC the data disappears and the user will not be able to find the stored information.

RAM is the main or working memory it allows the PC to work with more information. There are two main types of RAM in technology and both of the RAM use to hold data

DRM (Dynamic Random Access Memory)

SRAM (Static Random Memory)

The DRAM type of memory is used by today's personal computer which supports and stores temporary information. Each DRAM part is included of small storage locations, each DRAM cell is referred to as Bit (binary digit) and usually employed to mention the smallest amount of state, when it holds beyond a certain level.

The SRAM type runs as higher clock speeds than the other memory. The speed rate of SRAM is measure by MHZ and it compares the speed with system bus speed, the SRAM also handle its input and output signals with the incoming clock that is used in the system board.


The BOIS is the collection of software utilities that forms part of the operating system. It is usually on a ROM chip that comes with computer, called the ROM BOIS. Being on ROM, the BOIS is not effect by power failure and makes it possible for the computer to boot itself. The BOIS boots up the PC, which is it start up the PC every time it is turned on. The BOIS checks actual hardware configuration against the configuration data. It ensures the integrity of computer system and therefore proves to be the most important diagnostic tool available to you. The BIOS also handle the input and out of computer, allowing the operating system to use particular features of hardware within configuration. When the computer is turned on, its memory is empty, apart from one set of hardwired instructions that are located at an address called the jump address. These important few instructions, when executed, will load the BOIS into memory. The computer jumps to the jump address, starts executing instructions and these results in the BOIS being loaded.

The loading of the BOIS is the part of booting up process during which the configuration of the computer is checked (during the post process) and the operating system loaded, so that everything is ready for the user to start work.

Cash Memory: byte or word transfer block transfer

Main memory



This is a very small amount of memory; the size of cache is usually less than 1MB. Cache memory is projected to supply memory access time approaching that of the fastest memories available. Cache usually supports a large memory size which is less expensive. The cache includes a copy of section of the main memory. When the processer try to run the byte or word of memory the cache always makes a move to make sure the word is delivered to the processer.

2.2 Secondary Memory:

The secondary memory is the slowest memory; this memory does not access to the CPU directly it performs when it is copied to the primary memory such as RAM. The secondary memory is the external types of memory such as hard drive, flash memory CD's or DVD's. The secondary memory is the non-volatile which means the data will remain unless it is erased by the user.

Hard Drive:

HHD or Hard disk drive is a vital part of personal computer every personal computer has a hard drive, hard drives usually used to store information or any data related to computers. The biggest advantage of hard drive is it allows the user to perform remarkable; the size of the hard driver depends on the size and the price of hard driver, the HDD is one of the major data storage devices in a personal computer all the software and other large files are usually stored in the hard drive. Hard disk drive comes in different shapes the largest possible hard drive comes in 5.25 inches with the adapter. The hard driver usually locates inside the CPU with cable that connects to the motherboard. The platters inside the hard drive are usually made of aluminium, VHS player are made to read the data on the tape and it also writes data to the platters.

Flash Memory;

The user can store any type of data and files into computer such as digital photographs, games, music files, PDF and other sort of media. The hard drive is very important in computers but sometimes the hard drive doesn't recognise all the files, the computer finds the backup copies and files though the flash memory storage device. The flash memory is the fastest memory available in computers and video game consoles system, usually used for easy and fast information. The flash memory sometimes takes control of codes such as basic input and outputs. Flash memory rewrites the BOIS meaning the flash memory can be written into blocks (rather than bytes) sizes and makes it easy for the user to update. Flash memory cannot be used as a RAM because the Random Access Memory is always addressable at the byte.


The USB drive is a plug and play moveable storage device which can be used as zip drive disk. The USB drive can be used by any personal computer, to use this portable device the user needs to insert it into the USB port, computer usually identify the device as removable disk. The advantage of USB drive is it doesn't need any output cables or any power supply to run them. USB drives are available in different sizes; the sizes are also available up to about 80 gigabytes (GB).

CD Drive:

CD-ROMs are originally designed to record programs and music videos. Now days the CD-ROMs usually used to store data and they also computer storages devices, A CD is arranged by using a high power infrared leaser to burn 0.8-micorn meters, to the CD a low power infrared leaser handle the steps. If a CD crashes all the stored data inside the CD will be despaired.

3. Support Elements:

3.1 Motherboard:

The motherboard or the main system board is the main circuit board of personal computer. The mother board contains the main components of computer such as the Central Processing Unit (CPU), the Basic Input and Output System (BOIS) and the memory. Motherboard usually controls all the input and output components of computer system, all the controllers' required all the devices such as disk drive, keyboard, mouse and the monitor which displays the screen. All the motherboards include connecters and slits to install the processer with memory slots and many more connectors to connect all the components with the motherboard controllers. Control of the motherboard devices are built in the chipset and BOIS program inside the motherboard which controls the main data in computer system. The system communication controls the statement between the user, PC and other computers through the motherboard. Motherboard plays the main role in your system's performance it allows the user to read out which type of component the system can have via its connectors or BOIS setting.

Image Showing Main Parts Of A Motherboard

3.2 Power Supply:

Power supply is extremely important component of computer they come in a black or silver coloured box, with the fan inside it and cables coming from it. Power supply runs the important job the main job of this component is to supply the power to the various components of the computer. There are two main types of power the internal and external.

The external power via the socket provides AC (alternating current), is the type electricity which is very quickly and provides the efficient way of supplying power over long distance. The internal or DC (direct current) is the other type of electricity which deals with negative and positive direction it usually runs from negative charge to positive charge and provides the power which only runs short distance to travel. Since PC components work on DC, and the power from the wall socket supplies AC, the power supply has to convert AC to DC. So, the power supply converts the incoming supply of the power to one that is needed the right type and the required voltage.

3.3 Expansion slots:

Inputs and outputs:

Key board:

Keyboard is one of the most significant hardware of personal computer. Keyboard usually connects to the computer motherboard through the back panel of the CPU (Central Processing Unit). This is an output device that takes information from the user designed with many buttons and function keys. This is main component of a computer system which generates the output information. The main used of the keyboard is to type a list of commends or other characters into a computer system. This output device is similar to the standard typewriter. Keyboard comes in many types; a standard keyboard contains numerous number keys and other keys.

Graphic card:

A graphic card is also one of the main components of computer; graphic card is the output device of computer that generates the output picture to the main screen. People usually use the graphic card to run their PC better and faster, graphic card has its own memory it usually use for gaming and video editing


CPU - Central processing unit

HDD - Hard disc drive

GPU - Graphics processing unit

RAM - Random access memory

GHz - Giga hertz

MB - Megabytes

CD - Compact disc

DVD - Digital versatile disc

NIC - Network interface card

FPS - Frames per second

RW - Re-Writeable

BOIS - Basic input output system

PCI - Peripheral component interconnect

IP - Internet protocol


Operating system (Internals and Design principles sixth edition by William Stallings.

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HARD DRIVE Bill Gates and the Making of the Microsoft Empire. By James Wallace and Jim Erickson.

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