Lesson Notes By Weeks and Term - Senior Secondary School 1

SUBJECT: ICT

CLASS:  SS 1

DATE:

TERM: 1st TERM

 
WEEK ONE

TOPIC: OVERVIEW OF COMPUTER STUDIES

Reference book: Hiit @ School, Computer Studies for Senior Secondary Education.

CONTENT

A computer is a device, which under the control of a stored program, can accept data in a prescribed form, process the data and supply the results as information in a specified form.

There are three points to note about this definition:

Computer is a device: it consists of electronic and electro-mechanical parts working together to process data.  These various parts are referred to as computer hardware. 

Computer processes data: a computer performs three major functions which are:

1. it accepts data
2. it processes data

iii. it supplies data or information (Output)

A computer is controlled by a stored program: a program is a set of instructions which tells the computer what to do. Another term for computer program is software. A program is usually stored in the computer’s memory while the instructions are being carried out. However, software can be placed in the computer’s memory, used, taken out, and re-used again whenever required.   Two main constituents of a computer: A computer system includes all the other things that make the computer to function. It consists of two major parts, namely:

1. hardware
2. Software

Computer Hardware: The computer hardware is the part of a computer system that you touch, see and feel. Computer hardware is divided into two main categories namely:

• System unit, and
• Peripherals.

The system unit is the electronic components such as CPU, primary memory and other devices that are used to process and store data.

The peripherals of a computer system are the input devices, output devices, secondary memory and communication devices. 

Examples of peripherals devices are: keyboards, monitors, drives (hard disk, CD, DVD, floppy, optical, tape, etc.), mouse, printers, modems, scanners, digital cameras and cards (sound, colour, and video) etc.

Computer software: is a collection of computer programs and related data that provide the instructions to a computer on what to do and how to do it. In other words software is a set of programs, procedures, algorithms and its documentation. In contrast to hardware, software is intangible, meaning it “cannot be touched”.

Types of Software:  software is divided into two major classes namely:

1. System software, and
2. Application software

System Software: is computer software designed to operate the computer hardware and to provide and maintain a platform for running application program/software. It includes a combination of the following: device drivers, operating systems like Windows, servers and utilities.

Application Software: it is also known as software application, application or app, is computer software designed to help user to perform a singular or multiple related specific tasks. Some examples of this category of software are: Business software e.g SAP, Computer-aided design e.g. Corel Draw, Databases e.g. Microsoft Access, Decision making software e.g. Microsoft Project, Educational software e.g. Microsoft Encarta, Image editing e.g. Adobe Photoshop, Mathematical software e.g. system calculator, etc., Word processors like MS Word, Spreadsheets like  MS Excel, Media players and database applications.

Characteristics of Computers: the principal characteristics of a computer are:

1. Speed: Computers operate at a very high speed measured as much as nano and pico second. A microprocessor for example process Millions of Instructions Per Seconds (MIPS) repeatedly with accuracy.
2. Accuracy: Computers produce accurate results when the right input is supplied for processing based on the general rule GIGO (Garbage In Garbage Out). Computer errors hardly occurs, numerous errors in computing are as a result of human factor.

iii. Storage: Computers are storehouse of data. Computers can store large amount of data on its storage devices. They generally have two types of storage devices viz. Primary and secondary storage devices.

1. Versatility: Computers are versatile machines. They have the ability to perform numerous tasks ranging from simple to complex tasks. They are generally used in variety fields of human endeavour such as banking, medicine, education, etc
2. Automation: The operations of a computer system are automatic. They require little or no human intervention for its operation.

EVALUATION

1a. Define Computer.

1b. State the three point to note about the definition of Computer.

2a.State the three major functions of Computer. 

2b. A computer is classified into _____ and _____.

READING ASSIGNMENT: HiiT @ School, Computer Studies for Senior Secondary Education. Chapter One, pages 2-3.

WEEKEND ASSIGNMENT

OBJECTIVES

1. Computer hardware is divided into__   a.)  2     b)    3   c)       4     
2. The ____ of the computer system are the input devices, output devices, secondary memory and communication devices.     a) peripherals             b) hardware            c) software 
3. ____ is a collection of programs that gives instruction to computers on what to do. 
4. a) peripherals             b) hardware            c) software
5. Which software is designed to operate the computer hardware? a) system b) application c) peripheral 
6. The following are application software except a)device driver b)  Ms Access c) Corel draw

THEORY 

1. List FIVE examples of hardware and software components of a computer.
2. State and explain briefly FOUR characteristics of a computer

3a. Differentiate between hardware and software.

3b. List FIVE peripherals examples