Lesson Notes By Weeks and Term - Senior Secondary 1

History of computing

Term: 1st Term

Week: 2

Class: Senior Secondary School 1

Age: 15 years

Duration: 40 minutes of 2 periods each

Date:

Subject:      Data Processing

Topic:-       History of computing

SPECIFIC OBJECTIVES: At the end of the lesson, pupils should be able to

1. Identify concrete device used for computing in pre-computing age
2. Discuss the concept of numbering system in pre-computing age
2. List some early computing devices.
3. Mention the name of the inventors of the early computing device.
5. State some of the use of the early computing device.

INSTRUCTIONAL TECHNIQUES: Identification, explanation, questions and answers, demonstration, videos from source

INSTRUCTIONAL MATERIALS: Videos, loud speaker, pictures, Data Processing for senior Secondary Education by Hiit Plc, WAPB Computer Studies for Senior Secondary I by Adekunle et al, On-line Materials.

INSTRUCTIONAL PROCEDURES

PERIOD 1-2

 PRESENTATION TEACHER’S ACTIVITY STUDENT’S ACTIVITY STEP 1 INTRODUCTION The teacher reviews the previous lesson on the introduction to data processing Students pay attention STEP 2 EXPLANATION He explains the numbering system in the pre-computing age and the use of the early computing devices used mentioning their inventors Students pay attention and participates STEP 3 DEMONSTRATION He discusses further the use of the early mechanical and electronic devices also mentioning their inventors. Students pay attention and participate STEP 4 NOTE TAKING The teacher writes a summarized note on the board The students copy the note in their books

NOTE

HISTORY OF COMPUTING

EARLY COUNTING DEVICES

In the early days of man’s existence on earth, counting and simple arithmetic were performed using different parts of the body and some other counting aids. The following are devices used by people of ancient times.

1. Fingers and Toes
2. Stone
3. Sticks
4. Pebbles
5. Cowries

DISADVANTAGES OF EARLY COUNTING DEVICES

1. They are difficult to carry about.
2. Counting and calculation takes a lot of time.
3. They are prone to mistakes.
4. They cannot be used to count or calculate large numbers.
5. Their results cannot be easily remembered.
6. They have no storage facilities.

EARLY MECHANICAL AND ELECTRONIC DEVICES

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.

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

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.

NUMBER SYSTEM (REVISION)

To effectively use the computer, it is therefore necessary to know how data

is represented and communicated to. 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.

EVALUATION:    1. List any four early counting devices

1. List any TWO disadvantages of early counting devices.
2. How does Abacus and Napier’s function?
3. What type of operation can Pascaline perform?
4. List four early mechanical and electronic devices and name their inventor

CLASSWORK: As in evaluation

CONCLUSION: The teacher commends the students positively