1. The beginning of electronic data processing
The American government wanted to count the population.
People went to each house with a questionnaire. (Where do you/ your parents come from?)
This process needed 8 years to finish.

2. Hollerith‘s punch card counting system
Hermann Hollerith developed a counting system based on punch cards.
You had to punch the card at a special place for each answer.
This process needed only two years.

3. Function of the punch cards
You put the punch cards in the reader, pull down the handle. Then needles can go through the punches on the cards, close contacts and count one „point“ higher on the counting clocks.

4. The ENIAC – the biggest calculator
The Electronic Numerical Integrator and Computer was a big computer built for the US army. (costs today ca. € ,05)
It has electron tubes. If one tube gets out of order then people must check all the tubes till they’ve found the defect tube. To avoid this they developed a program that pointed out the broken tube.

6. Building Kits
In the early days of home computers you could order them in a building kit ($ 450) that you had to assemble before using it.
This was the Altair 8800.
It could only run simple programs that were created with switches.
The final machine cost $ 750.

7. Modern computer Modern home computers are very useful.
You are able to play games or use other software.
You have access to the internet.
You are able to connect PC‘s.
You are able to control your PC via keyboard and mouse, moving, touching or mimics.

8. Parts of a PC

9. The end
Thank you for your attention! Do you have any questions?