Steem for begginers! What basically is steem

Steem is a cryptocurrency used to power the platform Steemit - an incentivized blockchain social media platform.
Users create and curate content on Steemit just like other social news platforms and get rewarded in Steem for their work.Steem is the fundamental unit of account on the Steem blockchain.
All other units (Steem dollars and Steem power) derive their value from the value of Steem.
There is no need to hold on to Steem in its cryptocurrency form, it should be used either to buy Steem power, Steem dollars or be converted to Bitcoins.
Steem increases in supply 100% each year. Steem was first published as a whitepaper in March 2016.
The currency and platform were in Beta until July 4th 2016.
STEEM DOLLARS:

Steem dollars are the units used to reward users for posting and curating content.
Each Steem dollar represents the amount of Steem equivalent to 1 USD.
Steem dollars (or SMD) were created so that users won’t be affected by the fluctuating exchange rate of Steem
Steem power (or SP) is a token symbolizing how much power you have inside the Steemit platform.
When you have a lot of SP your votes count more in the system. In fact you can’t vote if you don’t have any SP.
Increasing your SP is known as “powering up” and decreasing it is known as “powering down”.
The way to power down is basically to cash your SP into Steem.
This can be done over a preiod of 104 weeks (2 years) in order to insure that users don’t just cash out quickly and collapse the whole Steemit economy.
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