CHAPTER ONE

CLASSIFICATION OF COMPUTERS

Performance objectives

Student should be able to:

1. Classify computers by generations, size, and degree of versatility.
2. Identify five generations of computer
3. Describe the features of each generation

UNIT ONE: CLASSIFICATION OF COMPUTERS
1.1.    CLASSIFICATION OF COMPUTERS BY GENERATION

Based on the time of emergence, computers are grouped into four classes or generations. These generations are:-
1.1.1. First generation computers
1.1.2. Second generation computers
1.1.3. Third generation computers
1.1.4. Fourth generation computers
1.1.5. Fifth generation computers

1.1.1. First generation Computers- period between 1951-1958

Features of second generation computers

Some of the basic features of the first generation computers are:

1. Vacuum tubes (Figure 142) were used for data processing instead of gears, switches and other mechanical devices.
2.       The first generation computers are the first computers to have an internal storage facility, called magnetic drum.
3.       First generation computers are the first computers to use machine language, the lowest-level programming language understood by computers, to perform operations.
4.       Input device-Input was based on punched cards and paper tape
5.       Output-Output was displayed on printouts on papers.
Examples of first generation computers are ENIAC, EDVAC, and UNIVAC etc

Limitations of the first generation computers

Some of the limitations of the first generation computers are:
1.       The computers were huge- up to the size of a room
2.       The computers were slow
3.       The computers were expensive

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