https://www.bitcoinmining.com/

Where do bitcoins come from? With paper money, a government decides when to print and distribute money. Bitcoin doesn't have a central government.

With Bitcoin, miners use special software to solve math problems and are issued a certain number of bitcoins in exchange. This provides a smart way to issue the currency and also creates an incentive for more people to mine.
itcoin miners help keep the Bitcoin network secure by approving transactions. Mining is an important and integral part of Bitcoin that ensures fairness while keeping the Bitcoin network stable, safe and secure.