KYC2 refers to a level of the general KYC authentication system in the financial field. KYC's authentication system is similar to real-name registration system's authentication system in China. When a user registers for a transaction in OKCoin, he/she needs to provide the user's identity certificate, and then he/she can conduct the transaction after confirming his/her identity. OKCoin introduced the KYC authentication system into its platform and divided it into three levels, each of which corresponds to a different transaction limit.