A mining pool can be thought of as a gang or coalition ofm31s whatsminer many miners. To address this issue, many miners pool their computing power to form a large computing power organization, and mining profits are then distributed based on the percentage of computing power contributed by each miner, forming a community of interest. This is the pool for mining.

Are all cryptocurrencies created through mining?

No. It is determined by the consensus mechanism. It is determinedmining app by the consensus mechanism. Mining is generally required for PoW or other consensus measures (such as ipfs' PoSt), whereas coins with DPoS consensus, such as EOS, do not.

Furthermore, the majority of the recently popular STO model issued cryptocurrencies are generated directly in the securitization process rather than through mining.

In summary, with the exception of a few old cryptocurrenciesminer gate such as Bitcoin and some cryptocurrencies used for points, most cryptocurrencies are not generated by mining.

Is there any revenue for miners to mine after all 21 million bitcoins have been mined?

There is money. Mining revenue is primarily comprised of a mining reward and a miner's fee, so even after all bitcoins have been mined, miners will continue to earn a miner's fee and the bitcoin network will remain operational.

Other cryptocurrencies derived from PoW mining are in the same boat. After all cryptocurrencies have been mined, miners continue to earn a miner's fee.