STORAGE DEVICES

Alternatively referred to as storage, storage media, or storage medium, a storage device is a hardware device capable of holding information. There are two storage devices used in computers; a primary storage device such as computer RAM and a secondary storage device such as a computer hard drive. The secondary storage could be a removable, internal, or external storage. In the picture to the right, is an example of a Drobo, an external secondary storage device.
Without a storage device, you and your computer would not be able to save any settings or information and would be considered a dumb terminal. Below, are some additional examples of storage devices that are used with computers.

TYPES OF STORAGE

OUTPUT DEVICE

Any peripheral that receives or displays output from a computer. In the picture to the right, is an inkjet printer and a good example of an output device that can make a hard copy of anything on a computer. Below is a listing of all the different computer output devices found on a computer.

TYPES OF OUTPUT DEVICES

PROCESSOR

The processor (called CPU, for Central Processing Unit) is an electronic circuit that operates at the speed of an internal clock thanks to a quartz crystal that, when subjected to an electrical currant, send pulses, called "peaks". The clock speed (also called cycle), corresponds to the number of pulses per second, written in Hertz (Hz). Thus, a 200 MHz computer has a clock that sends 200,000,000 pulses per second. Clock frequency is generally a multiple of the system frequency (FSB, Front-Side Bus), meaning a multiple of the motherboard frequency.

With each clock peak, the processor performs an action that corresponds to an instruction or a part thereof. A measure called CPI (Cycles Per Instruction) gives a representation of the average number of clock cycles required for a microprocessor to execute an instruction. A microprocessorâ€(TM)s power can thus be characterized by the number of instructions per second that it is capable of processing. MIPS (millions of instructions per second) is the unit used and corresponds to the processor frequency divided by the CPI.

TYPES OF PROCESSOR

INPUT DEVICES

An input device is any hardware device that sends data to the computer, without any input devices, a computer would only be a display device and not allow users to interact with it, much like a TV. In the picture to the right, is a Logitech trackball mouse and an example of an input device. Below is a complete listing of all the different computer input devices that can be used on a computer.

TYPES OF INPUT DEVICES

APPLICATION SOFTWARE

An application is a program or group of programs designed for end users. Application software can be divided into two general classes: systems software and applications software. Systems software consists of low-level programs that interact with the computer at a very basic level. This includes operating systems, compilers, and utilities for managing computer resources.
In contrast, applications software (also called end-user programs) includes database programs, word processors, and spreadsheets. Figuratively speaking, applications software sits on top of systems software because it is unable to run without the operating system and system utilities.

TYPES OF APPLICATION SOFTWARE

             

SYSTEM SOFTWARE

System software is a program that manages and supports the computer resources and operations of a computer system while it executes various tasks such as processing data and information, controlling hardware components, and allowing users to use application software. That is, systems software functions as a bridge between computer system hardware and the application software. System software is made up of many control programs, including the operating system, communications software and database manager. There are many kinds of computers these days. Some of them are easier to learn than others. Some of them perform better than others. These differences may come from different systems software.

Three Kinds of Programs
Systems software consists of three kinds of programs. The system management programs, system support programs, and system development programs are they. These are explained briefly.

 
1.System Management Programs
These are programs that manage the application software, computer hardware, and data resources of the computer system. These programs include operating systems, operating environment programs, database management programs, and telecommunications monitor programs. Among these, the most important system management programs are operating systems. The operating systems are needed to study more details. There are two reasons. First, users need to know their functions first. For the second, there are many kinds of operating systems available today.
Telecommunications monitor programs are additions of the operating systems of microcomputers. These programs provide the extra logic for the computer system to control a class of communications devices.
 
2.System Support Programs
These are the programs that help the operations and management of a computer system. They provide a variety of support services to let the computer hardware and other system programs run efficiently. The major system support programs are system utility programs, system performance monitor programs, and system security monitor programs (virus checking programs).
 
3.System Development Programs
These are programs that help users develop information system programs and prepare user programs for computer processing. These programs may analyze and design systems and program itself. The main system development programs are programming language translators, programming environment programs, computer-aided software engineering packages.

TYPES OF APPLICATION SOFTWARE