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What is exactly Ether currency in Ethereum? Is it a token or a set of some functions that generate some tokens? If so, how many of those functions exist and what do they do? Are they hardcoded in the source code or are they programmed within the virtual machine? Because, Ether can not be a token, since tokens must have to have a finite amount in quantity according to the documentation I have read.
Or is it a contract address that does some token generation?