Steem Dollars are liquid stable-value currency tokens designed to be pegged to $1 USD. Steem Dollars can be traded with STEEM and transferred to other accounts for commerce or exchange.
MX is the proof of rights and interests of MXC trading platform itself. Its total circulation is 3 billion constantly and never be added. MX holders can enjoy a series of rights and interests including asset appreciation, rebates on platform revenue, supervision, voting, etc. MX can be obtained in two ways: mining and buying.