- 
  
  The first machine that actually approximated the idea of a computer. The machine was called the "Difference Engine"
- 
  
  Several machines had been built which rivaled the Analytical Engine in complexity.
- 
  
  Lee De Forest invented the electric tube.
- 
  
  A computer developed at Harvard University by Howard H. Aiken was the first programmed controlled calculator. Very close to a fully operated computer.
- 
  
  Development of transistor.
- 
  
  Microprocessors were developed.
- 
  
  they were developed
- 
  
  Cray 1 was discovered
- 
  
  The Commodore Business Machines introduced their first personal computer.
- 
  
  Apple II released.
- 
  
  They introduced a new computer called the TRS-80. It was less expensive than the Apple computer.
- 
  
  Intel introduced the 8086 microprocessor.
- 
  
  It was the most popular computer sold through out the 1970-1980's.
- 
  
  IMB asked Microsoft to help with the new invention of the PC. They agreed and it became one of the most popular products in the world.