Secondary storage

File compression.
- File compression is the process of condensing certain files to take up less space on a computer, disc or external storage device. Compression usually requires special formats and software, but there are many different versions available. Compressed files have to be expanded again to be used.

Head crash.
- A head crash is a hard-disk malfunction that is the result of the read-write head of the hard disk coming in contact with the rotating platter, causing probably permanent damage to the magnetic media on the platter surface.

Internet hard drive.
- It is known to solve the issue of data storage. The sole purpose of this is to access computer files from any computer as long as that computer has Internet access. Unlike your local hard drive, which may have a limited storage capacity, a competitive Internet hard drive provider will offer virtually unlimited disk space such as offered by LiveDrive.com.

Optical disc drive.
- Optical drives retrieve and/or store data on optical discs like CDs, DVDs, and BDs (Blu-ray discs) which hold much more information than classic portable media options like the floppy disc. Most optical drives can play and/or record onto a large number of different disc formats. Popular formats include CD-ROM, CD-R, CD-RW, DVD, DVD-RAM, DVD-R, DVD+R, DVD-RW, DVD+RW, DVD-R DL, DVD+R DL, BD-R, and BD-RE.

Solid-state storage.
- Solid-state storage is a nonvolatile, removable storage medium that employs integrated circuits (ICs) rather than magnetic or optical media. It is the equivalent of large-capacity, non-volatile memory. The main advantage of solid-state storage is the fact that it contains no mechanical parts. Everything is done electronically. As a result, data transfer to and from solid-state storage media takes place at a much higher speed than is possible with electromechanical disk drives.

Input and Output

Ergonomic keyboard.
- According to Wikipedia, an ergonomic keyboard is a computer keyboard designed with ergonomic considerations to minimize muscle strain and a host of related problems. 'Ergonomic considerations' is a phrase that can have many meanings so let's look at what a few of those are. Your hands, wrists, shoulders and back are the areas of your body most vulnerable to repetitive strain injury (RSI). This is due to how we sit and move about when using computers under normal circumstances.

Ink- jet printer.
- A type of printer that works by spraying ionized ink at a sheet of paper. Magnetized plates in the ink's path direct the ink onto the paper in the desired shapes. Ink-jet printers are capable of producing high quality print approaching that produced by laser printers. In general, the price of ink-jet printers is lower than that of laser printers. However, they are also considerably slower. Another drawback of ink-jet printers is that they require a special type of ink that is apt to smudge on inexpensive copier paper.

Laser printer.
- A printer that uses a laser and the electrophotographic method to print a full page at a time. The laser "paints" a charged drum with light, to which toner is applied and then transferred onto paper. This process can also be called electrophotographic.

Magnetic-ink character recognition.
- Magnetic Ink Character Recognition (MICR), as defined by the American National Standards Institute (ANSI), is the common machine language specification for the paper-based payment transfer system.  It consists of magnetic ink printed characters of a special design which can be recognized by high speed magnetic recognition equipment.  Line placement, character placement, skew and quality are several critical components of printing MICR; the line must be precisely positioned in the MICR Clear Band area. 

Optical-character recognition.
- Optical Character Recognition (OCR) uses a device that reads pencil marks and converts them into a computer-usable form. OCR technology recognizes characters on a source document using the optical properties of the equipment and media. OCR improves the accuracy of data collection and reduces the time required by human workers to enter the data.

Optical-mark recognition.
- Represents the process of capturing human-marked data from document forms such as surveys and tests.
Optical-mark recognition devices work with a dedicated scanner device that shines a beam of light onto the form paper. The contrasting reflectivity at predetermined positions on a page is then utilized to detect the marked areas because they reflect less light than the blank areas of the paper.

The System Unit

Flash memory
- Flash memory refers to a particular type of EEPROM, or Electronically Erasable Programmable Read Only Memory. It is a memory chip that maintains stored information without requiring a power source. It is often used in portable electronics, like MP3 players, and in removable storage devices. Flash memory differs from regular EEPROM in that EEPROM erases its content one byte at a time. This makes it slow to update. Flash memory can erase its data in entire blocks, making it a preferable technology for applications that require frequent updating of large amounts of data as in the case of a memory stick.

Graphic cards
- A graphic card (also video card) is a piece of hardware installed in a computer that is responsible for rendering the image on the computer’s monitor or display screen. The first consideration when buying a graphics card is to be sure it is capable of displaying the best resolution the monitor can support. The second consideration is on-board memory. A graphics card must work very hard to render images to the screen. Unlike text files, graphics images are much larger files consisting of great amounts of data that must be processed by the graphics or video card. A faster graphics card has its own resident memory chips to perform this function so as not to impinge upon the system’s random access memory (RAM). Less robust graphics cards have less resident memory and require sharing system RAM to process images.

Sound cards
- An expansion board that enables a computer to manipulate and output sounds. Sound cards are necessary for nearly all CD-ROMs and have become commonplace on modern personal computers. Sound cards enable the computer to output sound through speakers connected to the board, to record sound input from a microphone connected to the computer, and manipulate sound stored on a disk.

Network Interface card (NIC)
- A network interface card, more commonly referred to as NIC, is a device that allows computers to be joined together in a LAN, or local area network. Networked computers communicate with each other using a given protocol or agreed-upon language for transmitting data packets between the different machines, known as nodes. The network interface card acts as the liaison for the machine to both send and receive data on the LAN.

Plug & play
- Plug and Play (PnP) is a capability developed by Microsoft for its Windows 95 and later operating systems that gives users the ability to plug a device into a computer and have the computer recognize that the device is there. The user doesn't have to tell the computer. In many earlier computer systems, the user was required to explicitly tell the operating system when a new device had been added. Microsoft made Plug and Play a selling point for its Windows operating systems. A similar capability had long been built into Macintosh computers.

Bus line
- The bus lines are the communicating lines that connect different parts of the CPU to various other parts. In addition, the bus lines also link the CPU to different parts on the system board of your computer. The data flows in the form of bits along the bus lines. The bus lines are like multilane pathway which means that the more bus lines are on the system the greater is the rate of transfer of data along the bus, which means that the computer can run efficiently and will perform the operations at a faster rate.

HDMI
- HDMI stands for High Definition Multimedia Interface. 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. High Definition technology or HD has seen a rapid increase in consumer use especially with HDTVs, HD-DVD and Blu-ray players, HD camcorders and other HD components. HDMI was developed by Hitachi, Panasonic, Sony, Toshiba, Philips, Thomson and Silicon Image who came together in a conglomerate effort to simplify the task of connecting and synchronizing available HD components for the user's benefit.

Cache memory
- Cache memory is random access memory (RAM) that a computer microprocessor can access more quickly than it can access regular RAM. As the microprocessor processes data, it looks first in the cache memory and if it finds the data there (from a previous reading of data), it does not have to do the more time-consuming reading of data from larger memory.