Computer Hardware Parts

These hardware components are further divided into the following categories, which are:

Input Devices
Output Devices
Storage Devices
Internal Components

1. Input Devices

Input devices are those devices with the help of which the user interacts with the computer. Or, In other words, with the help of input devices, the user enters the data or information into the computer. This information or data is accepted by the input devices and converted into a computer-acceptable format, which is further sent to the computer system for processing.

Now we discuss some input devices:

Keyboard: It is the most common and main input device for computers. The data is inputted by typing on the keyboard. It consists of 104 keys in total. It contains numeric keys, alphabet keys, and different function keys as well. Earlier, it was connected to the computer via cable, now as technology has advanced, you can connect a keyboard using Bluetooth.
Mouse: A mouse is a kind of pointing device which is rolled over to control the cursor on the screen and it has functional keys like left, middle, and right buttons. Using these functional keys, on by the click of which an object is selected or to open a file by just a click of a mouse. It also consists of a sensor inside which notifies its speed to the computer and according to which the cursor is moved on the screen.
Scanner: As the name suggests, it scans images, documents, etc., and converts them into digital form and that can be further edited and used. It works just like a Xerox machine.
Track Ball: It is a device much like an upside-down mouse. It does not use much space for movement like a mouse. As the trackball remains stationary and the user moves the ball in various directions, it affects the screen movements directly.
Light Pen: It is a light-sensitive device and it is touched to the CRT screen where it can detect, a raster on the screen as it passes by and, with the help of this user can draw anything like lines, figures, or any objects.
Microphone: It is a kind of voice input system that can be attached to a computer system to record sounds. It converts human speech or voice into electrical signals. This electrical signal is processed by the computer and the word is recognized.
Optical Character Reader: It is used to detect alphanumeric characters that are written or printed on paper using a low-frequency light source. This light is absorbed by the dark areas and reflected by the light areas, now this reflected light is received by the photocells. It is like a scanner.
Bar Code Reader: It is used to read bar codes and convert them into electric pulse which will further processed by the computer. Here, the barcode is data that is coded into white and black lines(or light and dark lines).

2. Output Devices

These are the devices that are used to display the output of any task given to the computer in human-readable form.

Now we discuss some output devices:

Monitor: The monitor is the main output device. It is also called VDU(visual display unit) and it looks like a TV screen. The Monitor displays the information from the computer. It is used to display text, video, images, etc.
Printer: A printer is an output device that transfers data from the computer in a printed format by using text or images on paper. There are both colored and black & white printers. Further, there are also different types of printers, like Laser Printer, Dot-matrix printers, and Inkjet printers.
Plotter: It is similar to a printer but potters are large in size. A plotter is used to generate large drawings, architectural blueprints, etc. on paper and these are high-quality images and drawings and large in size.
Speakers: It is a very common output device and it gives sound as an output. Speaker is generally used to play music or anything having sound.

3. Storage Devices

There are some devices that are used for storage purposes and are known as secondary storage devices. Some of them were discussed below:

1. CD (Compact disc): A CD is circular in shape and made up of thin platted glass and plastic polycarbonate material. It has a storage capacity of 600 MB to 700 MB of data. It has a standard size of 12 cm with a hole in the center of about 1.5 cm and 1.2 mm in thickness. There are basically 3 types of CDs, which are:

CD-ROM (CD – Read Only Memory): Contents of this type of CD cannot be erased by the user. Only the publisher is allowed to access the data imprinted on this CD. CD-ROM is basically used for commercial purposes like for a music album or any application package by a software company.
CD-R (CD-Recordable): In this, content or data can be stored once. After that, they can be read many times but the data or content cannot be rewritten or erased. (Kind of one-time use)
CD-RW(CD-Rewritable): As the name suggests, this type of CD is used to rewrite the content or erase previous content and again write new content many times.

2. DVD (Digital Video/Versatile Disc): A DVD is the same as a CD but with some more features. A DVD comes in single and dual-layer formats. It has much greater storage capacity in comparison to CD. The storage capacity of a DVD with one-sided single layer is – 4.7 GB, one-sided double layer – 8.5 GB, double-sided single layer – 9.4 GB, and double-sided double layer – 17 GB. There are also some types in DVDs, which are :

DVD-ROM: In this type, the contents of the DVD cannot be written on or erased by the user. DVD ROM is used for applications and database for distributing them in large amounts.
DVD-R / DVD+R: DVD-R (DVD minus R) and DVD+R (DVD plus R) are two different kinds of discs and they are once recordable format. Also, they have no difference virtually.
DVD-RW / DVD+RW: This is a kind of rewritable disc and it allows up to 1,000 rewrites.
DVD-RAM: DVD RAM is accessed like a hard disk. It provides high data security and storage capacity. This is a kind of rewritable disc and it allows up to 1,00,000 rewrites.

3. Hard Disk: An hard disk is a non-volatile storage device that uses its read/write heads to store digital data on a magnetic surface of a rigid plate. It is generally 3.5 inches in size for desktops and 2.5 inches in size for laptops. A hard disk can be classified further into 3 types, which are:

Internal Hard Disk: It has a common storage capacity stated as GB or TB. A system case or cabinet is the place where it is located. It can perform faster operations and its storage is fixed. It is mainly used to store large data files and programs.
Internal Cartridges: The Internal hard disk can’t be removed from the system cabinet easily. To resolve this problem Internal Cartridges are introduced. So, Internal cartridges are easy to remove CDs. It has a storage capacity of 2 GB to 160 GB. It is used as an alternative to an internal hard disk.
Hard Disk Packs: It is used by organizations such as banks, and government sector organizations to store large amounts of data. It has a storage capacity of a range of PB( Peta Bytes).