Secondary Storage

File Compression

File compression is commonly used when sending a file from one computer to another over a connection that has limited bandwidth. File compression basically makes the file smaller, hence sending the file would be faster. However, when compressing the file and sending the file to another computer, the computer would have to have a program that will decompress the file to the normal size.

Head Crash

Head crash is referred to a serious malfunction of the disk drive. A head crash usually means that the head has scratched or burned the disk. In a hard disk drive, the head is microinches away from the disk. When the head gets misaligned and touches the disk, much of the data will be lost.

Internet Hard Drive

The main purpose of an Internet hard drive is to be able to access your computer files from any computer, as long as that computer has access to the Internet. An Internet hard drive will allow you to put your computer files into a remote hard drive, then retrieve the same files from another computer. An Internet hard drive has unlimited capacity or unlimited virtual disk space, hence a lot of files can be stored there.

Optical Disc Drive

An optical disc drive can retrieve or store data on discs like CDs, DVDs, Blu-ray discs which are also known as optical discs. These discs hold much more information than the older technology like the floppy disk. An Optical Disc Drive (ODD) uses laser light or electromagnetic waves as part of the process to read and write data to or from the optical disc. ODD is almost the size of a thick soft cover book where the front of the drive has a Open/Close button which will eject and retract the drive bay door. This door enables discs like CDs to be inserted and removed. The back of the ODD is connected to the motherboard. 

Solid-state Storage

A solid-state storage is a data storage device which is also a removable medium that has integrated circuits (IC) rather than optical or magnetic media. A solid-state storage has no mechanical parts. Everything is done electronically, hence data transfer is takes place at a much higher speed than electromechanical disk drives do. Because solid-state storage uses the same interface as hard disk drives, they easily replace them in most applications. 

Input and Output

Ergonomic Keyboard

Ergonomic keyboard is a type of keyboard that is split. These keyboards are made mainly to help people solve any problems they have with their wrists. Keyboards like these are not guaranteed to completely solve the problem, however it gives the user more comfort when typing.

Ink-jet Printer

Ink-jet printer is a type of printer that sprays ink on papers. Ink-jet printers are able to print in black and white and also in colours. These printers spray very small droplets of liquid (ink) onto a paper to create an image. The dots are extremely small, have very precise positions and contain different colours to create quality images.

Laser Printer

A laser printer is similar to that of a photocopy machine, the difference is that a photocopy machine uses a bright line to scan, however, a laser printer uses laser to scan. A laser printer basically uses a laser beam to project an image on a drum. Laser printers are generally faster than ink-jet printers and are used to produce an output of higher quality.

Magnetic-ink Character Recognition (MICR)

Magnetic-ink Character Recognition, also known as MICR uses ink that is magnetically chargable or toner to print numbers and special characters. It is usually used to print on the bottom of checks or other financial transaction documents. Numbers that are printed are usually account number from which the money will be drawn or transit of the cheque. MICR is more widely used in the banking industry because it allows fast and reliable document processing. 

Optical-character Recognition (OCR)

OCR is where a computer recognizes printed or written text characters. This involves photoscaning of the text by characters, analysis of the scanned-in image and translation of the character images into codes. For example, ASCII which is commonly used in data processing. For OCR processing, the scanned-in image is analyzed to identify each character or digit, then it is converted into a ASCII code. OCR is also used by libraries to digitize and preserve their holdings.

Optical-mark Recognition

Optical-mark Recognition, also known as OMR, is the process of capturing marked data (by humans) from document forms such as survey forms and test papers. OMR generally works with a scanner device that shines a beam of light onto the paper. The contrasting reflectivity on a page is then used to detect the marked areas because they reflect less light than the blank areas of the paper. OMR is more commonly used in schools to mark MCQ's, also known as multiple choice questions.



The System Unit

Flash Memory

Flash memory is a type of Electronically Erasable Programmable Read Only Memory. It is a memory chip. It maintains stored information without requiring a power source. Flash memory is often used in portable electronics like MP3 players and in removable storage devices.

Graphic Cards

A graphic card is also a video card which is a piece of hardware installed in a computer that is responsible in rendering images on the computer's monitor screen. A graphic card is basically an expansion card whose function is to generate and output images to a display.

Sound Cards

A sound card is also known as an audio card. It is an internal computer component that processes audio files to provide high-quality playback through the computer speakers. A sound card plays audio files, voice as well as music. The typical sound card has an interface which is available at the back of the computer with various input and output ports. The quality of the sound card and speakers both affect the overall sound quality of the computer system.

Network Interface Card (NIC)

Network Interface Card, or NIC is a device that allows computers to be joined together in a local area network (LAN). It is a computer circuit board or card that is installed in a computer. Computers typically contain a NIC specifically designed for the LAN transmission technology such as Ethernet. Network interface cards provide a full-time connection to a network.

Plug and Play

Plug and Play (PnP) is a capability that gives users the ability to plug a device into a computer and have the computer recognize that the device is there. It was developed by Microsoft for its Windows 95 and later operating systems. With this, the user is not required to explicitly tell the operating system when a new device had been added.

Bus Line

Bus lines are communicating electronic lines that connect different parts of the CPU to various other parts.  Bus lines also link the system unit to different parts on the system board of the computer. The bus lines are like multi-lane pathway which means that the more bus lines are on the system the greater is the rate of transfer of data along the bus. This also means the computer can run efficiently and will operate at a faster rate.

HDMI

HDMI is also known as High Definition Multimedia Interface. HDMI is an interface standard used for audiovisual equipment such as high-definition television and home theater systems. It is a compact 19-pin plug and cable for connecting High-Definition video and multi-channel audio-capable as well as helping to speed the convergence of computer and consumer AV products.

Cache Memory

Cache memory memory is extremely fast memory that is built into a computer’s central processing unit (CPU), or located next to it on a separate chip. The CPU uses cache memory to store instructions that are repeatedly required to run programs, improving overall system speed. This enables the CPU to not have to use the motherboard's system bus for memory transfer. Hence, the CPU is able to process data faster.