Friday, December 3, 2010

" Five example of Storage Devices "

                                                    * Storage Devices*


                   Main Storage
In the world of computing, main storage is understood to be the program addressable memory that houses the executables and data necessary to launch and run various systems and programs. More commonly referred to as primary storage or memory, main storage directly interfaces with the CPU, which reads the instructions connected with the executables and performs the tasks necessary to handle the data. All data necessary for the effective function of programs saved on the hard drive is maintained in the main storage.


                  Primary Storage               
Also known as internal memory and main memory, primary storage is a storage location that holds memory for short periods of times while the computer is on. For example, computer RAM and cache are both examples of a primary storage device. This type of storage is the fastest type of memory in your computer and is used to store data while it's being used. For example, when you open a program data is moved from the secondary storage into the primary storage.


             Internal Storage
Internal storage is a term typically applied to any internal computer or system hardware component dedicated to the storage of data. The most well-known component is the hard disk drive (or hard drive), but other components include system memory ("RAM") and the BIOS/EFI/CMOS chips. 



           Secondary storage device                    
 Also known as external memory and auxiliary storage, secondary storage is a storage medium that holds information until it is deleted or overwritten regardless if the computer has power. For example, a floppy disk drive and hard disk drive are both good examples of secondary storage devices. As can be seen by the below picture there are three different types of storage on a computer, although primary storage is accessed much faster than secondary storage because of the price and size limitations secondary storage is used with today's computers to store all your programs and your personal data.



                  USB Disk Security 
Usb Disk Security is the best antivirus software to permanently protect offline computer without the need for signature updates, but other antivirus software should update signature database regularly, and they cannot effectively protect offline computer. This light and easy to use solution is compatible with other antivirus software and doesn't slow down your computer at all. You pay USB Disk Security once and get it all; however, other antivirus products should be paid for updates every year.




" Five example of Output Devices "

                                                                *Output Devices*


                  Impact printers
Refers to a class of printers that work by banging a head or needle against an ink ribbon to make a mark on the paper. This includes dot-matrix printers, daisy-wheel printers, and line printers. In contrast, laser and ink-jet printers are nonimpact printers. The distinction is important because impact printers tend to be considerably noisier than nonimpact printers but are useful for multipart forms such as invoices. 


 
                Non impact printer
A type of printer that does not operate by striking a head against a ribbon. Examples of nonimpact printers include laser and ink-jet printers. The term nonimpact is important primarily in that it distinguishes quiet printers from noisy (impact) printers. 



                      
                       Page Printer

page printer is a type of computer printer that prints on cut sheet paper. A modern page printer may use any of various technologies, such as laser, LED or inkjet. Most modern computer printers are page printers.







                   Plotter   
 A plotter is a computer printing device for printing vector graphics. In the past, plotters were widely used in applications such as computer-aided design, though they have generally been replaced with wide-format conventional printers, and it is now commonplace to refer to such wide-format printers as "plotters," even though they technically aren't.




        
         Computer Output on Microfilm (COM)

Computerized system that converts online or stored data directly into microfilm, as images for archiving.



" Five example of Input Devices "

                                                     * Input Devices *

                


                   Computer Keyboard
A computer keyboard is an important device that allows a person to enter symbols like letters and numbers into a computer. It is the main input device for most compute.






Computer monitors


Originally computer monitors were used for data processing and television receivers for entertainment; increasingly computers are being used both for data processing and entertainment. Displays exclusively for data use tend to have an aspect ratio of 4:3; those used also (or solely) for entertainment are usually 16:9 wide screen, Sometimes a compromise is used, e.g. 16:10





Graphics tablet

A graphics tablet (also called pen pad or digitizer) consists of a flat surface upon which the user may "draw" or trace an image using an attached stylus, a pen-like drawing apparatus. The image generally does not appear on the tablet itself but, rather, is displayed on the computer monitor. Some tablets, however, come as a functioning secondary computer screen that you can interact with images directly by using the stylus.
 




Bar code Reader

A bar code reader (or bar code scanner) is an electronic device for reading printed bar codes. Like a flatbed scanner, it consists of a light source, a lens and a light sensor translating optical impulses into electrical ones. Additionally, nearly all bar code readers contain decoder circuitry analyzing the bar code's image data provided by the sensor and sending the bar code's content to the scanner's output port.



Optical Mark Recognition 
(also called Optical Mark Reading and OMR) is the process of capturing human-marked data from document forms such as surveys and tests.