The Steem cryptocurrency exists in two forms:
- Steem Power (SP) - Steem that is locked-in and cannot be sold or transferred. SP requires a 13 week period to power down in order to be sold. SP is necessary for Steem users to participate in upvoting for the distribution of the Steem reward pool. It is also needed for bandwidth to post to the Steem blockchain.
- Liquid Steem - Steem that is not locked-in so can be sold or transferred at any time.
Liquid Steem can be converted to SP through a process known as powering-up.
Steem posts are typically paid in Steem backed dollars (SBD) and Steem Power. However when the distribution of SBD reaches a certain limit then posts are also rewarded with some liquid Steem in place of SBD.
All Steem on crypto exchanges will be liquid Steem.