Here is how I describe in Haiku Steem vs Steem Power Vs Steem dollars. In a week, you'l be able to have a conversation with your current self and say it all makes sense.

https://steemit.com/steemit/@gikitiki/a-steemit-haiku

My Coles notes version:

• Steem = The currency. I think of it more as a commodity (i.e. gold) It has a price that fluxuates based on the market. It's usually valued against 1 BitCoin.
• Steem Power = Invested Steem. You've locked this away for at least 104 weeks. The more Steem Power you have, the higher your reputation will be. With a higher reputation, your upvotes will mean more.
• Steem Dollar = The quantity of steem that is roughly equivalent to $1 USD