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STEEM is the cryptocurrency of this platform or social network Steemit, obtained thanks to the posts or publications of the users through the votes. It has three assets, where they can be converted to each other.

STEEM:

• Liquid, exchangeable in exchanges (Bittrex, Poloniex, and BitShares OpenLedger).
• Its annual inflation is 100%.
• STEEM is like cash in a hyperinflation economy and can be used to buy SP and SBD.
• It can be transferred from an exchange to the user's wallet, who uses his or her account name as the address.
• You can convert bitcoins directly to Steem. Use the deposit option in the Steemit portfolio.
• It is recommended not to save, its fluctuation is very unstable.
• Transfer from user to another. Use the transfer option in the Steemit portfolio.

Steem Power (SP):

• It is not liquid, to obtain it implies a long-term commitment with Steemit.
• With more user's SP, the greater their rewards for curing content.
• Of all the new STEEM that is created, 90% goes to those who have SP, and 10% to content authors and content curators.
• It is acquired by making it "Power Up STEEM" or with a direct deposit of Bitcoin to the Steemit portfolio.

Steem Backed Dollars (SBD o SMD):

• Liquids, interchangeable in the internal market of Steemit.
• Designed to have a stable value of around USD $ 1. Current values ​​are listed here (see column "Feed").
• The owners receive 10% annual interest.
• They can be converted to STEEM directly in the portfolio. The conversion takes a week, and the price is the median price for that week.
• They can be transferred to other users. Use the Transfer option in the Steemit portfolio..
• SBDs are like bonds. If you save 1 SDB you are already lending the red Steem $ 1, and they do pay you a reward in return, but not as much as if you had SP. But on the other hand you have the benefit of liquidity and you can sell your SDB at any time, not every 104 weeks as SP.

Source of information the here