What is crypto currency mining?
In the world of crypto currencies it is similar to the manufacturing of gold coins. You first acquire the raw material. Then let your hardware process it and extract coins that cannot be duplicated to defraud innocent people.
Digital currencies consist of a complex set of calculations and results that represent a digital serial number for a crypto coin. The raw material is called the block. The blockchain is literally the chain of computed calculation results that ensure that trough the distributed knowledge of the currency network the coin can never appear twice.