What is the difference between STEEM, STEEM Power, and Steem Dollars?

 STEEM - STEEM is the base liquid currency token in the platform. STEEM can be powered up into STEEM Power, traded for Steem Dollars, and transferred to other accounts. It is a cryptocurrency token, similar to bitcoin.

STEEM Power - STEEM Power (abbreviated SP) is a measurement of how much influence a user has in the Steem network. The more STEEM Power a user holds, the more they can influence the value of posts and comments. STEEM Power is less liquid. If a user wishes to “Power Down” SP, they will receive equal distributions of the STEEM weekly, over a 13 week period.

Steem Dollars - Steem Dollars (commonly abbreviated SBD) 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. Steem Dollars may also be converted into STEEM in a process that takes 3.5 days. Steem Dollars can be used to buy things in marketplaces, such as PeerHub.com.