1. (What came before our modern time-saving devices)
History of Computers
(What came before our modern time-saving devices)
By Miss Hall and Mrs. Batchelor, 2014

2. Inventors of PRE-Computers
Inventions (Machine)
Ancient civilizations (e.g. Egyptians, Chinese)
ABACUS, a manual calculating machine
Blaise Pascal
PASCALINE, an accounting adding machine
Gottfried Leibnez
STEPPED RECKONER, a calculating machine
Joseph-Marie Jacquard
JACQUARD’S LOOM, an automatic cloth-weaver
Herman Hollerith
TABULATING MACHINE, to tally census results
Charles Babbage
ANALYTICAL ENGINE, DIFFERENCE ENGINE

3. The Abacus

4. PASCAL and LEIBNIZ

5. Jacquard’s loom

6. Hollerith’s & Babbage’s machines

7. GENERATIONS OF COMPUTERS
First Generation
( )
Second Generation
( )
Third Generation
( )
Fourth Generation
(1971- present)
Vacuum Tubes
Transistors
Integrated Circuits
Microprocessors
Big and Clumsy
High electricity consumption
Larger AC units were needed
Lot of electricity failure occurred.
Smaller transistors were used
Core memory was developed.
Faster than first generation computers
Integrated circuits developed
Power consumption was low.
100 times faster than the second generation
Development of portable computers
Floppy disks, optical disks then flash memory became the popular storage media

8. 1st & 2nd generation

9. 3rd & 4th generation

10. Super Computer
Supercomputers – are the largest, fastest and most powerful computers at present.

11. Mainframe Computers
Mainframe – these computers are very expensive and can handle more than hundred users at a time. They are found in large organization such as banks.

12. Mini Computers
These become outdated and are rarely used today. They were very popular in the 1960s. They take up less space, may fit on a desk or take up the space of filing cabinet. Modern versions would be something like servers

13. Microcomputer
This type of computer includes those for general purpose and for business needs. They are usually called PC’s (Personal Computers) based on the microprocessor.

14. Types of Computers MICROCOMPUTER MINICOMPUTER MAINFRAME SUPERCOMPUTER
Desktop, laptop, palmtop
About the size of a small filing cabinet
Large office desk dimensions
Roomful of large filing cabinets
SIZE 1
10-100
500-thousands
USERS
Microseconds
Under 100 nanoseconds
Under 70 nanoseconds
Under 15 nanoseconds
SPEED
Joysticks, modems, keyboard, printer, disk drives, monitor, etc.
Terminals, printers
Magnetic tape drive
Special high-performance devices
PERIPHERALS
Dust-free, anti-virus, disk protection
Air- conditioning and security recommended
Special cooling, fire protection, security required
ENVIRONMENT
Cheapest
Small businesses or departments use it
Often used as part of a network in medium to large businesses, e.g. banks
Severe heat buildup, for superior (scientific) applications
NOTES

15. REFERENCES
THE END..