Transcript
Fundamentals of Fundamentals of ITIT
Fundamentals of Information Technology
INFORMATION: Consists of facts and items of knowledge. It can be anything that has meaning to people. Usually information is expressed in words and numbers. However, it can be expressed in other forms, such as sounds, measurements or pictures.
EXAMPLE:•A list of names and addresses•The contents of a letter•The words of a song•A map
DATA: Is information in which it can be processed.
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EXAMPLE•A word processed letter stored on a floppy disc•A song written as sheet music so that it can be played.•A telephone conversation converted to electrical signals to be sent down the wires.
PROCESSING OF INFORMATION
Information processing is the organization, manipulation and distribution of information.
Sorting a list of names and address into alphabetical order.
Producing a letter with a word processor, saving it on floppy disc and then sending it by electronic mail.
Transmitting a conversation over the phone system.
DATA PROCESSING CYCLE
* Data received by a computer via its input devices
* Stored in memory prior to processing
* Data get processed
* Results sent to the output devices
Memory
Processing
INFORMATION TECHNOLOGY
Information technology (IT) is all types of equipment and programs which are used in the processing of information.
ex:A computer.A calculator.A fax machine.A telephone.
Uses Of Information Technology The term ‘information technology is
also used to refer to the uses of this technology. The main types of use involved are:
Presentation of information. Handling information. Searching data, sorting it into order
and analyzing Producing modules of real situations Data communication. Control and measurement
DIGITAL AND ANALOGUE DATA
A device is digital if some quantity in it can be set to a number of different separate values or states. Data is then represented by combinations by these values. Usually the devices are binary and data is represented as a succession of 1s and 0s.
An analogue device is one in which data is represented by some quantity which is continuously variable. The value of a data item at a given time is represented by the size of the quantity measured on a fixed scale.
A Computer is a programmable, multipurpose machine that accepts data (e.g. raw data, facts & figures) and processes, or manipulates it into information we can use, such as summaries or totals
A COMPUTER
E.g. An Automated Teller Machine (ATM) computes the deposits and withdrawals to give you the total in your account.
A COMPUTER (ISO)Computer: (ISO) A programmable functional unit that consists of one or more associated processing units and peripheral equipment, that is controlled by internally stored programs and that can perform substantial computation, including numerous arithmetic operations or logic operations, without human intervention during a run.
A computer may be a stand-alone unit or may consist of several interconnected units.
PHYSICAL COMPONENTS OF A COMPUTER
The physical components of a computer system such as the computer itself, its inner components and peripherals are called hardware.
An example of Motherboard
Input devices are used to feed data and instructions to the computer system.
Input devices provide the interface between the outside world and the computer system for this purpose.
INPUT DEVICES
Input Devices
Tracker ball
Mouse
Touch sensitive pad
Light pen
Graphics tablets (digitizers)
Touch screen
Magnetic stripe reader
Barcode readers
Optical character readers (OCR)
Optical mark readers (OMR)
Microphone
Voice recognition
Electronic point of sale terminal (EPOS)
Electronic fund transfer at point of sale (EFTPOS)
Video digitizer
Scanner
Digital cameras
Output Devices
Output devices provide results in a suitable form after data processing. In many cases this will be in the form of hard copy or on a screen.
Liquid crystal display (LCD) screens
Laser printers
Inkjet printers
Color laser printers
Color inkjet printers
Classification of Computers
1.Classification according to the logic used
Analog Computers:- These computers recognize data as a continuous measurement of a physical property ( voltage, pressure, speed and temperature).
Example: Automobile speedometer
Digital Computers:- These are high speed programmable electronic devices that perform mathematical calculations, compare values and store results. They recognize data by counting discrete signal representing either a high or low voltage state of electricity.Digital computers are grouped into two categories:o General purpose computerso Special purpose digital computers
1. Classification according to size
Super Computers:- are widely used in scientific applications such as aerodynamic design simulation, processing of geological data.
Mainframe Computers:- are usually slower, less powerful and less expensive than supercomputers. A technique that allows many people at terminals, to access the same computer at one time is called time sharing. Mainframes are used by banks and many business to update inventory etc.
Minicomputers:- are smaller than mainframe, general purpose computers, and give computing power without adding the prohibitive expenses associated with larger systems. It is generally easier to use.
Small Computer Systems:- is the smallest, least expensive of all the computers. Micro computers have smallest memory and less power, are physically smaller and permit fewer peripherals to be attached.
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