The steemit platform has three tokens: Steem(the cryptocurrency of steem blockchain),Steem based dollars(SBD) which are tokens worth approximately 1 USD and the last one is STEEMPOWER(SP). Steem power is the influence token on the steemit platform slightly relatable to reddit's karma. SP measures your influence of your upvotes on the platform, more you have it more the value of your upvote. It also influences your reward share in similar fashion. The value of SP is the same as Steem(cryptocurrency).

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