Ether Classic was formed after the Ethereum blockchain hard forked in the summer of 2016. The hard fork was the result of a policy decision to rollback the DAO attack in which $60M of investor funds were stolen. Due to this decision not having the full backing of the community, a separate branch of Ether forked away, now known as Ethereum Classic (ETC).
Ethereum Classic is a separate blockchain to Ethereum, and the two should not be confused as they are now wildly different. Ethereum has the backing of the Ethereum Foundation, its development team and the roadmap outlined in Ethereum’s crowdsale – which includes the introduction of Proof of Stake, Sharding and so on. Ethereum Classic does not share these attributes, however there is much speculation over ETC’s future value as a digital asset, with Barry Silbert – owner of Grayscale Investments LLC – forming the Ethereum (ETC) Investment Trust.