Authors of Posts and Comments get paid in Liquid STEEM ( STM ) or STEEM DOLLARS ( SBD )which can be bought, sold or traded immediately. These same Authors also get paid in non transferable Steem Power, the more Steem Power ( SP ) a person has the more 'power' they gain across the Steemit platform.
Curators or Voting gets just a small reward in untradeable Steem Power (SP) , it takes 104 weeks ( two years ) to convert all of your SP into Liquid STEEM (STM). SP decays away and is lost slowly over time and gains a very high interest rate to maintain a Steemians value in untradeable SP.
Steem is tradeable but gains no interest payments, it is best to either Power Up Stm into SP or to sell or transfer Steem away since its value decays over time.
SP is about more power for Steemit platform functions and rewards only. SP also decays away but has an annual interest reward of 120 percent to keep up with the loss of current Steem due to the new creation of new steem by the Steem Miners. This keeps the total amount of Steem under the maximum Steem market cap.
SBD can be bought or sold or traded as a cryptocurrency immediately. There is a maximum that can be held to prevent massive sell offs by short trading etc to keep the website stable long term. SBD attracts interest at 10 % per annum.
The better a person interacts and presents helpful quality material and presentations on the Steemit platform the higher the potential rewards might be earned by efforts or luck by Steemians.
Steemit rewards people based on various factors and pays Steemians in a cryptocurrency that an be sold or traded with some long term holdings restrictions. However Steemit gives every person a chance to build up a stock market portfolio of cryptocurrency without any risk of their own money. Simply people can be financially rewarded for investing their spare time into a fun and innovative Social Media platform called Steemit.com ! ! !
In case your thinking scam or ponzi or whatever to date Steemit has received nods of approval or large traditional companies and does not ask your name, credit details nor bank account, Steem you earn can be traded for Bitcoin and sold for hard cash fiat money. Some places are now accepting Steem as a payment option for goods and services . . . Be assured legal Courts of Law have ruled cryptocurrency as money and as personal assets ! ! !
What can be better than that people spending their spare time to expand their knowledge base and working together to make a difference to others while earning the chance of gaining some sort of personal and monetary reward ! ! !
Put another way ; Steemit gives average people the chance to play StockBroker and trade 'Shares' or just build up their own " investment portfolio " for free without risking any of their own Real Life hard earned assets : )