https://www.investopedia.com/tech/how-does-bitcoin-mining-work/

 What is Bitcoin Mining?

Cryptocurrency mining is painstaking, costly and only sporadically rewarding. Nonetheless, mining has a magnetic appeal for many investors interested in cryptocurrency because of the fact that miners are rewarded for their work with crypto tokens. This may be because entrepreneurial types see mining as pennies from heaven, like California gold prospectors in 1849. And if you are technologically inclined, why not do it?