Introduction to

Introduction To Computer Science
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Production Credits
Production Credits
Author
Dessalegn Mequanint
Peer Reviewer
Florence Tushabe
AVU - Academic Coordination 
Dr. Marilena Cabral
Overall Coordinator Applied Computer Science Program 
Prof Tim Mwololo Waema
Module Coordinator
Victor Odumuyiwa
Instructional Designers 
Elizabeth Mbasu
Benta Ochola
Diana Tuel
Media Team
Sidney McGregor 
Michal Abigael Koyier
Barry Savala
Mercy Tabi Ojwang
Edwin 
Kiprono 
Josiah 
Mutsogu
Kelvin 
Muriithi 
Kefa 
Murimi
Victor Oluoch Otieno
Gerisson Mulongo
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Copyright Notice
This document is published under the conditions of the Creative Commons 
http://en.wikipedia.org/wiki/Creative_Commons
Attribution 
http://creativecommons.org/licenses/by/2.5/
Module Template is copyright African Virtual University licensed under a Creative Commons 
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Supported By
AVU Multinational Project II funded by the African Development Bank.
Introduction To Computer Science
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Table of Contents 
Table of Contents 
Foreword 2
Production Credits 
3
Copyright Notice 
4
Course Overview
13
Prerequisites 
13
Materials 13
Course Goals 13
Units 14
Assessment 14
Schedule 15
Readings and Other Resources 17
Unit 0: Pre-Assessment 
19
Unit Goals 19
 
Key Terms 19
1 What is a Computer? 20
2 What is Computer Science? 20
3 What is Information Technology? 20
4 What is Information and Communication Technology? 21
Binary Number System 21
Assessment: Basic Terms and Binary Number System 22
Grading scheme 
22
Answers 23
References 23
Unit 1: Introduction to Computer Systems 
24
Unit Goals 24
 
Key Terms 24
Learning Activity: What is a Computer? Characteristics of Computers, 
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Types of Computers 25
1. What is a Computer? 
25
Characteristics of Computers 
25
Types of Computers 
26
Classification by the Method of Operation (processing) 
26
Classification by purpose of application 
27
Classification by Physical Size, Capacity and Performance 
28
What is Computer Science? 
28
Activity Conclusion 
29
Answers 29
Assessment: Reflective Activities 
29
Learning Activity: History of Early Days Computers 30
History and Evolution of Computer Systems 30
History of Computer Systems 
30
Activity Conclusion. 
31
Assessment: Reflective Activities 
31
Answers 32
Learning Activity 3: The Advent of Modern Days Computers 32
Activity Conclusion 
34
Answers 34
Assessment: Reflective Activities 
34
Learning Activity: Creating a Summary for the Unit 35
Introduction 35
Instructions 35
Activity Assessment Criteria: Summary completeness and 
readability. 35
Assessment 35
Grading scheme 
37
Answers 37