Ethereum Classic is an uncensored, public and decentralized blockchain platform that emerged after the Ethereum hard fork. Ethereum Classic is known as a security-focused, non-censorship, public and decentralized Blockchain platform where applications can be run. Ethereum Classic can be defined as Ethereum without hard fork. In order to describe the emergence of Ethereum Classic, we need to talk about the DAO attack. DAO means a collective decision-making mechanism that can work decentralized and with a voting system, without the need for any documents. DAOs initially collect funds through smart contracts and distribute tokens to participants. When the fund collection ends, the DAO starts to work, token holders can vote on decisions regarding the organization, and they have a say in the spending plan of the money collected in the DAO. So DAOs are run only by the community.