Intro to Computers 01/07/2013
CRT (old monitor)
CPU = most important and expensive part
Memory = next most important and expensive part
CPU socket = brain of computer – generates a lot of heat – needs a fan to cool it down
A computer is an electronic device that can store, retrieve and process data. All its parts are
categorized into one of the following:
2. Input device
3. Output device
4. Auxiliary storage device – performs quick calculations etc.
Main memory is very fast and expensive while storage devices are cheap. Also, main memory is
extremely volatile – it is easier to lose data on it, and it could crash.
CPU: Fetches, decodes and executes instructions from the main memory.
Main memory: Circuits that can store data. The CPU obtains data from it very quickly.
Blaise Pascal invented the mechanical calculator.
Charles Babbage = father of computers, who originally created the Analytical Engine – the first general
purpose digital computer (1833). It wasn’t actually built till 1943 (in the form of Harvard Mark I).
Ada Lovelace was an English mathematician and writer mainly known for her work on Babbage’s
Analytical Engine. She is known as the first programmer.
There are 5 generations of computers:
• Vacuum Tubes (19401952)
• Transistors (19521964) • Large Scale Integrated Circuits (19641971)
• Very Large Scale Integrated Circuits (19711990) (no airconditioning required from this stage
• Microprocessor, higher storage capacity, multimedia (risk generation)
Kinds of computers:
1. Supercomputer = requires its own special room with airconditioning as it generates a lot of heat. It
is super as it performs hundreds of millions of orders in a second. It contains thousands of CPUs. In
1997, Deep Blue, a supercom