SOFTWARE

The intangible part of computer. It tells what a computer supposed to carry out and how to do it.

A collection of computer programs together with the related data..

Categories of computer

•System software

•Application software

•Programming language

SYSTEM SOFTWARE ; controls and maintains the operations of the computer and its devices.

APPLICATON SOFTWARE; makes users more productive and assists them with their tasks.

PROGRAMMING LANGUAGE; enables people to communicate instructions to a computer

TYPE OF STORAGE

1.Hard drives

2.Flash memories

3.Optical discs

4.Other types

•  tape

•  magnetic stripe cards and smart cards

•  microfilm and microfiche

•  enterprise storage

 

 

  LABEL  PRINTER

Small printer that prints on adhesive-type material

Most also print bar codes

Postage printer has built in digital scale and prints postage stamps

PLOTTER

Sophisticated printer used to produce high quality drawings

Large format creates photo color prints

MULTI FUNCTION PERIPHERAL

Also known as all-in-one device- a single device that provides the functionality of printer, scanner, copy machine and sometimes a fax machine.

THERMAL PRINTER

Generates images by pushing electrically heated pins against heat sensitive paper.

Dye-sublimation printer also called digital photo printer uses heat to transfer dye to specially coated paper.

   

  

MOBILE PRINTER

Small, lightweight,  battery-powered, printer that allows mobile user to print from notebook computer, tablet Pc, or PDA while travelling.

PRINTER VARATIES

IMPACT PRINTERS

Characters/ graphics are formed on the paper by physic contact between ink ribbon and paper

Examples are

1.Dot matrix printer

2.Line printer

●

  NON-IMPACT PRINTERS

The sharpness and clarity of printout

PRINTERS

A  printer produces text and graphic or papers.

Printed information is called hard copy.

•Impact printers

•Non-impact printer

•Thermal printer

•Mobile printer

•Label printer

•Plotter

•Multi function peripheral

OUTPUT

Output is a DATA that has been processed into a useful form.

An output device is any type of hardware component that conveys information to one or more people.

OPTICAL SCANNER

Data is captured directly from a source document such as order forms, invoices paychecks,photos,etc...

Scanners

Optical scanner

Optical reader

Barcode reader

Magnitude stripe and reader

MICR

Input

Input is any data instructions entered into the memory of a computer can be the form of programs commands and user responses.

An input device is any hardware is any hardware component that allows user to enter data and instructions into a computer.

 

                           REGISTERS

A processor register is a small amount of storage available as part of a CPU or other digital processor.
it is for

• special purpose
• high speed
• temporary storage

                      MAIN MEMORY

there a two types of memory
       RAM (random access memory)
       ROM ( read only memory)
  
                   RANDOM ACCESS MEMORY

the term random access means that any word in the memory may be accessed, without having to go through all the other words to get it. this memory is an integrated circuit chip.
RAM has two types

• DRAM
• SRAM

              READ ONLY MEMORY

ROM chip is installed by the manufacturer inside the computer. its also called firmwire, it retains instructions in a permanently accecible non volatile form. when the power in the computer is turned off, the instructions stored in ROM are  not lost.

                                   MOTHERBOARD
motherboard is a main board in system unit. it contains chips, integerated circuits,  and transistors. also its called as System board.
                                 
                                   PRCESSOR
The processor is the most impotant part of the computer. it process the data and controls the computer.
powerful computers used as servers often have more than one processor.
                                
                                  CENTRAL PROCESSING UNIT
CPU is the brain of the computer system. it contols the computer operations. such as   make decisons, makes all sorts of  calculations etc.
it function

• converts data into information
• contol center

• set of eloctranic circuitry that executes stored program instructions.

System unit

The system unit is a case that contains electronic components (processor,memory,expansion cards etc..) and most storage devices..

SYSTEM UNIT COMPONENTS

• processor
• memory module
• expansion cards

• ports and connectors..

Super computer

A supercomputer is a computer at the frontline of current processing capacity, particularly speed of calculation.
Supercomputers are used for highly calculation-intensive tasks such as problems including quantum physics, weather forecasting, climate research, molecular modeling (computing the structures and properties of chemical compounds, biological macromolecules, polymers, and crystals), and physical simulations (such as simulation of airplanes in wind tunnels, simulation of the detonation of nuclear weapons, and research into nuclear fusion)

Mainframe Computer

Mainframes are powerful computers used primarily by corporate and governmental organizations for critical applications, bulk data processing such as census, industry and consumer statistics, enterprise resource planning, and financial transaction processing..

Midrange server/ computer

A medium-sized computer system or server. Midrange computers encompass a very broad range and reside in capacity between high-end PC servers and mainframes. For example, IBM's Power Systems are its midrange line for both business and scientific applications. Formerly called "minicomputers," which were hosts to dumb terminals connected over dedicated cables, most midrange computers today function as servers in a network.

Personal Computer

A personal computer (PC) is any general-purpose computer whose size, capabilities, and original sales price make it useful for individuals, and which is intended to be operated directly by an end-user with no intervening computer operator. In contrast, the batch processing or time-sharing models allowed large expensive mainframe systems to be used by many people, usually at the same time. Large data processing systems require a full-time staff to operate efficiently.

Mobile device / Computer

Mobile computing is a form of human–computer interaction by which a computer is expected to be transported during normal usage. Mobile computing has three aspects: mobile communication, mobile hardware, and mobile software. The first aspect addresses communication issues in  infrastructure networks as well as communication properties, protocols, data formats and concrete technologies. The second aspect is on the hardware, e.g., mobile devices or device components. The third aspect deals with the characteristics and requirements of mobile applications

Embedded Computer

An embedded system is a computer system designed to do one or a few dedicated and/or specific functions often with real-time computing constraints. It is embedded as part of a complete device often including hardware and mechanical parts....

Categories of computer

1. Embedded computer
2. Mobile device / computer
3. Personal computer
4. Mid range server
5. Main frames
6. Super computers

Computer architecture

Computer architecture is the field of study of selecting and inter-connecting hardware components to create computers that satisfy  functional performance and cost goals...