BMX is an ERC20 based token issued by BitMart Exchange with total volume of 1,000,000,000. First issued as BMC in December 2017, BitMart changed the name of the token in January 2018 as BMX. You may find that the symbol name displayed in the smart contract and block explorer as BMC, but the actual symbol name we use is BMX. The reason is: our toke was named BMC, but then we find that 'BMC' has been used by another project, so we have to change the symbol name of our token to 'BMX'.
CRYPTO20 is an autonomous crypto-only index fund that tracks the top 20 cryptocurrencies in the same way the S&P500 tracks the top 500 US company stocks. C20 is the fund’s token, and represents an investor’s share in the fund. Token-holders are able to liquidate the C20 token for their share of the underlying assets via the smart contract.