Ethereum Classic can be considered a different cryptocurrency from Ethereum. They have different Blockchains and are independent of one another. But they have the same features and even shared the same blockchain (Ethereum) until the hard-fork was introduced, which caused the blockchain to split in two (ETC and ETH). A hard fork was the best possible way to reverse the illicit and inhumane actions of the hackers that invaded Ethereum, and at last, ETC was born.