Millions of jobs related to manufacturing of hardware and software products related to computer technology have been created worldwide in the last 2 to 3 decades.
Computers are very efficient in the sense that what was done manually by several people and took days to finish, can now be achieved in minutes, hence a large increase in productivity and substantial decrease in costs.
Computers help a lot in weather forecast where complex equations are involved. It is impossible to solve these equations manually. Even with powerful computers such as supercomputers, it takes many hours to get reliable predictions when it comes to severe weather including tornadoes, floods and tsunamis and hence avoid loss of life and property.
The lower prices and the high performance of todays' personal computers together with the development of the internet gave the opportunity to millions of people, worldwide, to work online in such activities as online shopping, advertising, education, etc ...