TOPCOIN is a type of crypto-currency, released February 2nd, 2014, with which you can make instant person to person payments, anywhere in the world. TOPCOIN also has a built in staking feature that allows you to collect more coins if you have some in your wallet!
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.