Introduction to computer science dessalegn Mequanint Yehuala Foreword

particular bit pattern in RAM.
√ Executes programs by doing one instruction after the next in a serial manner
using a fetch-decode-execute cycle.

---

---

Computer System
41
Assessment: Reflective Activities
• What does the stored program concept mean?
• What is the operation the control unit is responsible for?
• What is the operation the ALU is responsible for?
Answers
• Unlike some electronic devices such as calculators computers are capable of
storing their own instructions attributed to Von Neumann’s architecture - the
stored-program concept.
• The control unit is responsible for managing the process of moving data and
program into and out of memory.
• The ALU is responsible for arithmetic and logic operations
Learning Activity: Software Systems 
Introduction
The computer hardware refers to the physical components of a computer system. For the
individual components of a computer system to perform a task they need to be instructed. The
finite set of instructions (steps) that a computer system follows to perform a given task is called
a program. For any program to be executed first it should be loaded in the memory.
A Software is therefore defined as a collection of programs that directs a computer to
accomplish a given task[5].
Software Types
Software is divided into two types:
• System Software, and
• Application Software.

---

---

Introduction To Computer Science
42
System Software
System software is designed to facilitate the work of the computer’s hardware. The following
are activities a system software is responsible for:
• It is responsible for organizing and managing the computer’s hardware;
• It acts as intermediary or interface between the user and the computer hardware
• It makes what it looks to be a complex hardware more users friendly.
System software is further divided into:
•