SSS 3 Computer Notes

Senior Secondary School (SSS) Three Lesson Notes in computer studies/ICT have been prepared on the following topics below

Introduction to World Wide Web (WWW)

WWW is an acronym that stands for World Wide Web).
WWW is part of the internet that contains linked b, images, sound, and video documents. It is also defined as an information space where documents and other web resources are identified by URLs, interlinked by hypertext links, and can be accessed via the Internet. ...

Cables and Connectors

Network Cables are mediums through which information usually moves from one network to another.
Types of Network Cables
Network cables include the following types:
a. Unshielded Twisted Pair (UTP) Cables
b. Shielded Twisted Pair (STP) Cables
c. Coaxial Cables
d. Fibre Optics
e. Telephone...

BASIC Programming III (One Dimensional Array)

An array is a list of variables of the same kind. A variable is a name the computer assigns value to.
To create an array, the DIM (dimension) command is used.
The DIM statement has the following syntax: DIM arrayName(n).
For example DIM Score (5) will reserve 6 spaces, Score (0) Score (1), Score (2), Score (3), Score (4) and Score (5) in the memory to hold value. The number inside the parentheses of the individual variables are called subscripts, and each variable is called a subscripted variable or element...

High Level Language

High Level Languages are programming languages that allow for programs to be written in forms that are readable to human beings.
A high-level language is a programming language that, in comparison to low-level programming languages, maybe more abstract, easier to use, or more portable across platforms...

Data Representation

Data representation refers to the methods used to internally represent information stored in a computer. Computers store a lot of different types of information which include: Numbers, Text, Graphics, and Sound. At least all seem different to us. However, all types of information stored in a computer are stored internally in the same format: a sequence of 0’s and 1’s. ....

Networking

A computer network consists of a collection of computers, printers and other equipment that are connected together so that they can communicate with each other.
It is also defined as a group of two or more computer systems linked together.
Computer Networking is the scientific and engineering discipline concerned with communication between computer systems. ...

Database

Database is a collection of related data organized for rapid search and retrieval. It can also be defined as a persistent, logically coherent collection of inherently meaningful data, relevant to some aspects of the real world. ...

Introduction to CorelDraw

Definition of Graphics Packages
A graphics package is an application that can be used to create and manipulate images on a computer.
There are two main types of graphic packages:

1. Painting packages: A painting package produces images by changing the colour of pixels on the screen.
A pixel is the smallest unit of a digital image that can be displayed and represented on a digital display device. ...

Overview of Number System

A number system is a collection of symbols used to represent small numbers, together with a system of rules for representing larger numbers.
There are various number systems, some are examined below:
Decimal Number System
The decimal numeral system (also called base ten or occasionally denary) uses various symbols (digits) for no more than ten distinct values (0, 1, 3, 4, 5, 6, 7, 8, and 9) ...

Security and Ethics

Data security is the practice of keeping data protected from corruption and unauthorized access.
Sources of Security Breaches
1. Viruses, Worms and Trojan horses: Viruses, worms and Trojan Horses are all malicious programs that can cause damage to your computer, but there are differences among the three, and knowing those differences can help you to better protect your computer from their often damaging effects.
Virus: A computer virus attaches itself to a program or files so it can spread from one computer to another, leaving infections as it travels. It is important to note that a virus cannot be spread without a human action, (such as running an infected program) to keep it going. ...