I don't know much about blocktrade, but cryptocurrencies work through building blocks by adding transactions from mining game. The block name is added to denote the blocks from distributed systems. Among the miners, who is able to mine and add to the block in mining auction, is rewarded with transaction fees (STEEM POWER here). Steemit using blockchain for transaction of "upvotes" and "stem" between members . Anyone, can add to it please do so.