What is a computer?
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Subject classification: this is an information technology resource . |
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Educational level: this is a secondary education resource. |
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Resource type: this resource is a lesson. |
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Completion status: this resource has reached a high level of completion. |
Objective
Familiarize the student with the basics of computers. This should give the student a stepping stone to use when learning more specific details about computer hardware.
What is a Computer?
A computer is an electronic device that takes input such as numbers, text, sound, image, animations, video, etc., processes it, and converts it into meaningful information that could be understood, presenting the changed input (processed input) as output. All numbers, text, sound, images, animations, and video used as input are called data, and all numbers, text, sound, images, animations, and video returned as output are called information.
- The data consists of numbers, text, sound, images, animations, and video.
- The process converts numbers, text, sound, images, animations, and video (data) into usable data, which is called information.
- The information consists of numbers, text, sound, images, animations, and video that has been converted by the process.
- The data is inserted using an input device.
- The central processing unit (CPU) converts data to information.
- The information is put on an output device.
A storage device is an apparatus for storing data and information. A basic computer consists of 4 components: an input device , a CPU, output devices, and memory.
- One of the most common input devices is the keyboard, used to enter text.
Keyboard (not all are the same)
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Keyboard with a Swedish layout
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Keyboard with Danish layout
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Optimus-113 keyboard with color screens in each key
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Apple keyboard with German layout
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Symbolics space-cadet keyboard
- A computer will process data differently based on the kind of data being handled, using a set of instructions called a program or routine.
Computer Case
The CPU, motherboard, memory and any internal components are typically put into a computer case/housing.
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Macintosh Performa 6400
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Power Macintosh 7600
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Power Macintosh 8100
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Power Macintosh 8200
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Fujitsu-Siemens Celvin-1
Monitor
• A computer monitor is the most commonly used graphical output device, for the information processed by the CPU.
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A Fujitsu computer monitor
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A CRT computer monitor
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KDS XFlat monitor, screen
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LCD, SyncMaster 710
Computer System

The minimum requirements for a functional computer system include; a keyboard, a case/ housing containing a CPU and memory (although the case itself isn't strictly necessary), and a monitor. The data is usually entered via the keyboard and the information is usually presented through a screen; however, information can also be presented through speakers, braille displays, or any other output devices.
The way components inside a computer fit together helps describe how the computer works.
Data comes in through an Input Device, and is sent to the CPU by Memory. The CPU processes the data, based on the input data and the program which is installed in the computer memory. When the CPU has finished processing the data, it is presented through the output device as information. The information can be stored in the computer memory or presented through an Output Device.