Computer Science An Overview

Allen C.-H. Wu Computer Science Department Tsing Hua University

Preface

• 4 Beginning computer science students need exposure to the breadth of the subject in which they are planning to major.

• 4 A foundation from which they can understand the relevance and interrelationships of future courses.

2

Introduction

4 Computer science is the discipline that seeks to build a scientific foundation for a variety of topics. 4 Computer science provides the underpinnings for today’s computer applications as well as the foundations for tomorrow’s applications.

3

The Study of Algorithms

4 An algorithm is a set of steps that defines how a task is performed. 4 In the domain of computing machinery, algorithms are represented as programs within computers.

4 Algorithms + Data Structure -> Programs, Programs -> Software <=> Hardware.

4

The Study of Algorithms

4 The study of algorithms began as a subject in mathematics.

4 The major goal is to find a single set of directions that described how any problem of a particular type could be solved. 4 E.g., the long division algorithm and the Euclidean algorithm.

5

The Study of Algorithms

4 Machine Architecture - 1) manipulation (Ch. 2) 4 Software

. Data storage (Ch. . Data . . . .

Operating systems and networks (Ch. 3) Algorithms (Ch. 4) Programming languages (Ch. 5) Software engineering (Ch. 6) 4 Data Organization

. Data structures

• (Ch. 7) (Ch. 8)

. File structures 6 . Database

structures (Ch 9)

The Development of Algorithmic Machines

4 Abacus.

4 Babbage’s difference engine.

4 Jacquard’s loom.

4 Herman Hollerith (holes in paper cards).

4 Mark I at Harvard University.

4 ENIAC at U. of Pennsylvania.

7

The Evolution of Computer Science

Execution of

Execution of Limitations of Algorithms Analysis of Communication of Discovery of Representation of

8

The Evolution of Computer Science

Software
Hardware

Languages Algorithms Applications

9

Abstraction and Other Issues

• 4 Abstraction - the distinction between the external properties of a component and the internal details of the component’s construction.

• 4 Ethical issues.

• 4 Social issues.

4 Legal issues.

10