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The 4 Functions of a Computer

Alfred is a long-time teacher and computer enthusiast who works with and troubleshoots a wide range of computing devices.

The four functions of a computer actually explain the core reasons why it was built. They include:

  • Data input
  • Data processing.
  • Information output.
  • Data and information storage.
An illustration of the four functions of a computer

An illustration of the four functions of a computer

To illustrate the four functions of a computer, we can take a look at the basic steps we all go through to produce a LETTER on the computer.

It starts when the user composes, inputs and edits sets of letters, numbers and symbols using a keyboard. The raw data is then processed and viewed real-time via display hardware.

Finally, the user may choose to print the letter onto paper, or better still send it via electronic mail to designated recipients.

The same data and information can be retained digitally in disk drives and other media for future reference.

1. Data Input

Every computer is designed with data input as a first function, an activity which is accomplished via input devices.

Data entry is done manually, automatically or both. Manual input is done via add-on peripherals like the keyboard, mouse and stylus. Input can also be accomplished via vocal dictation applications and body gestures peripherals like Kinect and biometric devices. Elsewhere, data input is also done using secondary storage media and networking interfaces.

Application software used for this purpose will also dictate what data is entered. Word processing software is designed to input basic alphanumerical data, while a photo editing application is used to input and manipulate images.

This data may be entered into a database, spreadsheet or other forms of a computerized work area.

Automated applications and robotics can also be used to intelligently feed data into the computer on station or remotely. As an example, tallying of electoral process can be accomplished remotely and automatically.

Laptop keyboard and touchpad

Laptop keyboard and touchpad

2. Data Processing

Data processing is the core function of a computer. Processing involves manipulation of raw data into before converting it into meaningful information. Usually, data is in raw form, and will thus undergo processing before dissemination for user consumption.

The 'brain' of the computer where data is processed is referred to as the microprocessor. It is also commonly known as the central processing unit (CPU) or accelerated processing unit (APU).

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The processing chips in modern personal computing devices continue to evolve and outperform its predecessors. One particular evolution is the merger of microprocessor and graphics processing unit (GPU) into what is now known as accelerated processing unit. The merger allows for the integration of powerful graphics processing abilities inside the traditional arithmetic and logical computations of the processor.

Besides the microprocessor, the dynamic random access memory (DRAM) and static random access memory (SRAM) are integral parts of data processing. Data entered via input devices is stored temporarily in DRAM, then transferred to SRAM from where the microprocessor manipulates it.

An AMD microprocessor, inserted onto a laptop motherboard socket

An AMD microprocessor, inserted onto a laptop motherboard socket

3. Information Output

When raw data has been manipulated by the microprocessor, the outcome is meant to be disseminated for useful purposes. The output is thus referred to as information and is beneficial to the computer user.

Processed data or information can be,

  • viewed as alphanumeric, images and video via a display hardware
  • listened to as audio files by use of a speaker
  • printed as hard copy output onto paper
  • printed as 3D models
TV output on a computer screen

TV output on a computer screen

4. Data and Information Storage

The fourth and equally very important function of a computer is data and information storage. After sleepless nights of video and animation creation and editing, the user wants to have the finished product stored for future dissemination and additional editing.

A computer can store information internally and externally. The hard disk drive (HDD) and/or solid-state disk drive (SSD) are internal storage devices and serve to protect and house all data and information on a computer. In bigger systems, the RAID system is used. Multiple disk drives operate simultaneously to ensure data and information integrity.

External storage is achieved through accessories that attach externally to the computer. They include external drives and optical disks.

Better still data and information can be stored online in cloud solutions for a fee or for a fee if large space is required.

Storage integrity is a crucial phase that can actually determine the worth of a computer system. In any case, what use is a computer without data and information?

Information created in the computer can be stored onto CDs and DVDs

Information created in the computer can be stored onto CDs and DVDs

This article is accurate and true to the best of the author’s knowledge. Content is for informational or entertainment purposes only and does not substitute for personal counsel or professional advice in business, financial, legal, or technical matters.

© 2013 Alfred Amuno


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What are the four functions of a computer referring to hardware and software used to perform such functions

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Inputting is computer function

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State 5function that a digital computer carry out?

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