The Computer System

• Data and Information

    In day-to- day language, the words "DATA" and " INFORMATION" may   
    mean the same thing. But in computer jargon they do not.

  For example lets take the numbers 290781, it can be an I.D. card number   
  or a date or either a passport number, so when this number cannot be  
  determined for sure we say that it's a DATA. Now if the same number is 
  shown as 29/07/81 then one can recognises this, as a date so it becomes   
  information. A quick way to remeber it is :

                 DATA + STRUCTURE = INFORMATION
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• A Computer

A digtal computer is a machine that can be programed to accept data [ input] and process it into information [ output] and where necessary the computer may also use storage devices to store information.
                      
                        INPUT -> PROCESS -> OUTPUT

A computer is a device that accepts input,

process data, stores data and produces output.

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    Here are some words that are important to learn an be able to distinguish 

                                       from one an another :)

• Basic Functions of a Computer

Input : Entering of data into a computer

Output : Getting processed data out of the computer

Processing: Transform data into meaningful information

Storage : Saving the data in the computer for later use

Retrieval : Data is fetched from the computer and read

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Hardcopy is when you send data to a printer or plotter to make a paper copy.

Softcopy is when the computer display the data on a monitor screen.

Storage devices is used to hold data permanently, so you can save it and retrieve it later

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  Examples of INPUT, OUTPUT, STORAGE DEVICES

Input:

    keybored                                                       Mouse

 

Output:

Monitor
                                                                             

   

                                                                                                    Printer  

                   

   

  Storage Devices :

Hard Disk                                  CD'S

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Here is a video to show you different kinds of computers :

There are also two more types of computers which are :  

 Supercomputers : supercomputers are very powerful computers, which occupy special air-conditioned rooms, and are often used for research.

Embedded Computers : are a vast number of modern devices contain some form of built-in computer, [camera, washing machines, telephones, hi-fi system] etc.

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Hardware and Software

 A computer is divided into two categories :

1. Hardware 
2. Software  

(1) Hardware, are the physical units that make up a computer system, in 

     other words, all those untis that can be seen and touched. 

(2) Software, is another word for programas. There are two main types:

1. Application software 
2. System software

(1) Application software is the kind of software that people use to preform a general-purpose task, such as word processing software.

(2) System Software is the software that the computer uses to manage its own internal activites and run application software. The Operating System (OS)is the most important software.  

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Main Components of a Computer   

1. CPU [ processor] : this is the brain of the computer it's speed is measured in Mhz or Ghz
2. Main Memory [primary storage] : is part of a computer system where data amd insturctions are held for use by the CPU and where the CPU puts results it generates.
3. Backing Storage : is a means of storing large amounts of data outside the main storage.
4. Bus : is a data roadway along which data and commands travel.

In a computer there are three different types of buses :

• The address bus
• The data bus
• The control bus

                            

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Well thats all for today i hope it helped you :) BYE.