© Thomas Kabalin
Information
Technology
Introduction
Input device: any hardware or peripheral device that allows you to enter data into a
computer or interact with a computer
Storage device: a hardware device that is used for storing data
Processing device: a hardware device that receives the data, performs a set of instructions,
and then returns the processed data to the RAM
Output device: a device that formats and presents data in a form understandable to a user
Communication device: a hardware device capable of transmitting a signal over a wired or
wireless connection
Random Access Memory (RAM): a hardware device, usually on the motherboard, that allows
information and data to be temporarily stored and retrieved while the computer is on
Computer
Hardware Software
1. Processor (CPU + GPU) Application System
2. Memory (RAM + Cache)
3. Storage
General Model of a Computer
ICT and IT
Information and Communication Technology refers to technologies that capture, transmit
and display data and info electronically and includes all devices, applications and networking
elements that allow people to connect in a digital world
It is a combination of computer-based technologies (computing devices) with
communication technologies (cellphones, internet)
The hardware, software and systems needed to communicate electronically
Made up of:
o People: supply data and make decisions from the output based on the results of
processing from an ICT system
o Hardware: input devices, storage, processor, output devices, communication devices
o Procedures: to determine what needs to be done and when; causes passing of data
(or information) between people
o Software: computer programs which provide the step-by-step instructions to
complete the task
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, © Thomas Kabalin
o Data: raw material processed by the system to provide the information for the
output (includes sounds, images, videos)
ICT systems need to receive, store, manipulate and transmit data – done by computers
Computers are programmable electronic devices designed to accept data, perform
prescribed mathematical and logical operations at high speed and display the results of
these operations
Computers refer to hardware – cannot function alone
Start functioning when they receive data to process
Data is store, manipulated according to instructions revived, and sent back to the user
IT: the development, maintenance and use of computer systems, software and networks for
processing and communicating data
General Model of a Computer
Storage
Memory
Input CPU Output
Communication
IPOS (IPO) = receives input, processes according to user instructions, provides an output,
stored in desired format
Input – data (raw facts and figures that can be processed using arithmetic and logical
operations to obtain information)
Output after processing – information
Hardware & Software
Computer needs both to function (interdependent)
o Hardware: physical components of the computer
o Software: application software and system software (OS) refers to programs used to
direct the operation of a computer (also has instructions on how to use it)
Hardware needs software because it relies on the processed instructions to provide input
Software needs hardware to process the user’s instruction
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Hardware
Input devices – hardware devices that allow you to input data into, or interact with, a
computer (e.g. touchscreen keyboard, mouse, keyboard)
Storage device – hardware device that stores data for later use (hard disk drive and solid-
state drive)
Random Access Memory (RAM) – fast, temporary form of storage
o All data and instructions currently being executed are stored in RAM
o It is volatile – data is erased when computer is turned off
o Also called Memory
Processing devices receive data from the RAM, perform sets of instructions and return the
processed data to the RAM
o Central Processing Unit (CPU) processes general instructions – every application uses
it to collect, decode & execute instructions
o Graphics Processing Unit (GPU) processing instructions that create pictures on the
screen (3d games use GPU to create images)
Output devices return the computer’s instructions, as results, to the user (e.g. monitors,
printers)
Communication device – hardware device capable of transmitting an analogy or digital signal
over a wired or wireless connection (e.g. modem, network interface card (NIC))
Software:
Software: the set of instructions a computer uses to complete any instructed task
Software is operated by the hardware
System software
Manages and controls computer and the hardware of the computer
OS is most important type of system software (e.g. Windows, Mac OS, Linux)
Designed to control and coordinate tasks and functions of computer hardware
Application software
Program built for a specific purpose
Lets the user accomplish a function or create content
Needs system software to function
Multiple applications packaged together = application suite
E.g. Google Chrome, Skype, Games, Mobile apps
Shareware, Freeware, FOSS, Proprietary software
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