Ethereum Classic (ETC)
Ethereum Classic was the original Ethereum blockchain. After the DAO hack (see the "notorious hacks" section), the developers made a decision to fork the project, to reverse the effects of the DAO. The project now known as "Ethereum" was the result of that forked blockchain, and Ethereum Classic is the original chain. Supporters of Ethereum Classic adhere to the concept that "code is law" and, while regrettable, the DAO hack should not have been reversed as it destroyed the notion of immutability for the project.
Mining/Staking
Ethereum Classic uses the same Proof of Work mining algorithms as Ethereum.
Development Team
This project is not officially supported by the Ethereum Foundation.
Criticisms, Caveats, and Competitors
The post-DAO forked version of Ethereum is much more well known and widely utilized. Ethereum Classic has very little real-world adoption.
Additional Resources
The project's main website: https://ethereumclassic.github.io
Link to Wikipedia Page: https://en.wikipedia.org/wiki/Ethereum_Classic
Link to Reddit Community: https://www.reddit.com/r/EthereumClassic
Link to Twitter account: https://twitter.com/eth_classic
Link to Team information: None, no further development
Link to data on Live Coin Watch: https://www.livecoinwatch.com/coins/ETC
Whitepaper: https://trello.com/c/ffNTcsQU/10-ethereum-classic-whitepaper