Lesson Notes By Weeks and Term - Senior Secondary School 1

SUBJECT: DATA PROCESSING

CLASS:  SS 1

DATE:

TERM: 1st TERM

REFERENCES

• Data Processing forSenior Secondary Education by Hiit Plc.
• A Handbook on Computer Studies by NiyiAdekolegan.
• On-line Materials.

 
WEEK TWO

TOPIC: HISTORY OF COMPUTING

EARLY MECHANICAL COUNTING/CALCULATING DEVICES

1. Abacus
2. Slide rule

EARLY ELECTRO-MECHANICAL COUNTING DEVICES

1. John Napier bone
2. Blaize Pascal machine
3. Gottfried Leitbnitz machine
4. Joseph Jacquard Loom
5. Charles Babbage analytical machine

EARLY ELECTRONIC COUNTING DEVICES:

1. Herman Hollerith punch card
2. John Von Neumann machine

Man has put in every effort to have better methods of calculations. As a result of man’s search for fast and accurate calculating devices, the computer was developed. Essentially, there are three kinds of calculating devices: manual, mechanical and automatic.

ABACUS

The first calculating device was probably Abacus. The Chinese invented it. It is still in use in some countries because of its simple operation. It is made up of a frame divided into two parts by a horizontal bar and vertical threads. Each thread contains some beads. It was used to calculate simple addition and subtraction.

NAPIER’S BONE

The need for a better calculating device was felt as time passed. John Napier, a Scottish mathematician, invented a set of eleven rods, with four sides each which was used as a multiplication tool. These rods were made from bones and this was the reason why they were called Napier Bones. The rods had numbers marked in such a way that, by placing them side by side, products and quotients of large numbers can be obtained.

EVALUATION

1. Explain types of early counting devices.
2. How does Abacus and Napier’s function.

PASCALINE

The first mechanical calculating machine was invented in 1642, by Blaize Pascal, a French mathematician. Numbers were entered by dialling a series of numbered wheels in this machine. A sequence of wheels transferred the movements to a dial, which showed the result. 

Through addition and subtraction were performed the normal way, the device could perform division by repeated subtraction and multiplication by repeated addition.

LEIBNITZ CALCULATING MACHINE

Gottfried Wilhelm Von Leibnitz invented a computer that was built in 1694. It could add and after changing some things around, it could multiply. Leibnitz invented a special stepped gear mechanism for introducing the added digits and this is still being used.

JACQUARD’S LOOM

Jacquard’s loom was one of the first machines that were run by a program. Joseph Jacquard changed the weaving industry by creating a loom that controlled the raising of the thread through punched cards. Jacquard’s loom used lines of holes on a card to represent the weaving pattern.

PUNCHED CARD

During the years1920 and 1930, the punched card system developed steadily. A standard card was divided into 80 columns and 12 rows. Only one character could be represented in the 80 columns, thus providing a maximum of 80 characters per card. Punching one, two or three holes in any one column represented a character. Holes were punched into a blank card by a punch machine whose keyboard resembled that of a typewriter.

CONCLUSION

We have learnt about the various calculating devices and the various ways they perform their operations. We learnt also that Abacus was the first calculating devices.

NUMBER SYSTEM (REVISION)

To effectively use the computer, it is therefore necessary to know how data is represented and communicatedto it. There are different ways of representing data in the number system, namely:

1. Decimal System
2. Binary System
3. Octal System
4. Hexadecimal Number System.

GENERAL EVALUATION

1. How does Abacus and Jacquard’s loom function?
2. What type of operation can Pascaline perform?
3. Explain the four number system.
4. List any four early counting devices.

READING ASSIGNMENT

Read Chapter 1, Pg1-3, A Handbook On Computer Studies, By NiyiAdekolegan.

WEEKEND ASSIGNMENT

1. Napier’s  Bones had ……..A.  9 rods   B.  11 rods   C.  10 rods   D.  12 rods
2. Jacquard’s loom was used in the  ……A.  mechanical industry  B.  weaving industry  C.  food industry  D.  all of the above
3. ……. was the first calculating device. A. Napier’s Bones  B. Punched card  C.  Abacus  D. Slide rule
4. The octal number system has a radix of …….  A. 7  B.  10  C.  16  D.  8
5. The Decimal Number is in Base ……A.  2     B.  8   C.  10   D.  16

THEORY

1. Describe a standard Punch Card.
2. Explain Decimal Number system.