1. What is a computer ?
- A computer is a device that accepts information (in the form of digitalized data) and manipulates it for some result based on a program or sequence of instructions on how the data is to be processed.
- A computer is an electronic device that manipulates information, or data. It has the ability to store, retrieve, and process data.
- You can use a computer to type documents, send email, and browse the Web. You can also use it to handle spreadsheets, accounting, database management, presentations, games, and more.
2. Why to use a computer ?
- work faster and more precise
- use one piece of information again in different documents
- make calculations without mistakes and correct your English spelling
- present your work better and more professional
- make as many copies and different versions of documents as you like
- store and keep track of your (electronic) documents
- send (electronic) mail and documents to distant relatives and business relations within a matter of minutes
- find information you need, available on one of the millions of computers that are worldwide connected to the internet
3. Basic parts of computer
- The basic parts of a computer are the computer case, monitor, keyboard, mouse, and power cord. Each part plays an important role whenever you use a computer.
The computer case is the metal and plastic box that contains the main components of the computer. It houses the motherboard, central processing unit (CPU), power supply, and more.
Computer cases come in different shapes and sizes. The front of the case usually has an on/off switch and one or more optical drives.
The monitor works with a video card, located inside the computer case, to display images and text on the screen. Newer monitors usually have LCD (liquid crystal display) or LED(light-emitting diode) displays. These can be made very thin, and they are often called flat-panel displays. Older monitors use CRT (cathode ray tube) displays. CRT monitors are much larger and heavier, and they take up more desk space.
Most monitors have control buttons that allow you to change your monitor’s display settings, and some monitors also have built-in speakers.
The keyboard is one of the primary ways we communicate with the computer and enter data. There are many different types of computer keyboards, such as wired, wireless, ergonomic, and multimedia. Although there may be differences in the location of some keys or features, keyboards are very similar and allow you to accomplish basically the same tasks.
The mouse is a peripheral that is known as a pointing device. It lets you point to objects on the screen, click on them, and move them. There are two main types of mice: optical and mechanical. The optical mouse uses an electronic eye to detect movement and is easier to clean. The mechanical mouse uses a rolling ball to detect movement. Generally, a mechanical mouse is less expensive, although it may require regular cleaning to keep it working properly. Traditionally, a mouse connects to the computer using a USB or PS/2 connection. However, you can also buy a wireless mouse, which can reduce clutter on your desktop.
4. What are peripheral devices ?
- A peripheral device connects to a computer system to add functionality. Examples are a Graphic Card, Joystick, CD-ROM, printer and scanner.
- A computer peripheral is a device that is connected to a computer but is not part of the core computer architecture. The core elements of a computer are the central processing unit, power supply, motherboard and the computer case that contains those three components.
- Peripheral devices can be external or internal. For example, a printer is an external device that you connect using a cable, while an optical disc drive is typically located inside the computer case. Internal peripheral devices are also referred to as integrated peripherals.
5. What are input devices?
- An input device is known as device that provides input to a computer. The two most common input devices are a keyboard and mouse.
- Without input device, data is not feed to the computer and computer is useless.
- Types of input devices
- Barcode reader
- Business Card Reader
- Digital camera and Digital Camcorder
- Finger (with touchscreen or Windows Touch)
- Gamepad, Joystick, and Paddle
- Graphics tablet
- Light gun and light pen scanner
- Magnetic ink (like the ink found on checks)
- Magnetic-stripe reader
- Medical imaging devices (e.g., X-Ray, CAT Scan, and Ultrasound images)
- Microphone (using voice speech recognition)
- Mouse, touchpad, or other pointing device
- Optical Mark Reader (OMR)
6. What is an output device?
- An output device is any device used to send data or information from a computer to another device, network or user.
- Examples include monitors, projectors, speakers, headphones and printers.
7. What is an storage device?
- A storage device is used for storing and extracting data and information.
- It can hold and store data and information temporarily and permanently.
- It can be internal or external to a computer.