Mining is the process by which new units of cryptocurrencies, like Bitcoin, are introduced into the system. It is also the method used to verify and add transactions to the public blockchain, ensuring the integrity and security of the entire network.
Miners use specialized equipment, often referred to as "ASICs" (for "Application-Specific Integrated Circuit"), to solve complex cryptographic puzzles. By solving these puzzles, they validate transactions and add them to the blockchain. As a reward for this work, they receive newly created cryptocurrencies as well as the fees associated with the transactions they have validated.
There are "pools" or "mining cooperatives", which are groups of miners working together to increase their chances of earning the mining reward. The earnings from these pools are then distributed among the miners based on the computing power they contributed.
It's important to note that, at least in the case of Bitcoin, the mining difficulty adjusts automatically based on the total power of the network. This is done to ensure that the rate at which new Bitcoins are created remains constant, despite fluctuations in global mining power. Thus, the more miners there are and the more power they have, the more difficult it is to mine, ensuring a stable issuance of the currency.