Howdy Chels, SBD is Steem backed dollars. These can be traded for Steem. or Steem can be traded for SBD within the Steemit platform. When you have Steem, You can power up with it, When you power up the Steem, you increase your voting power (value of your vote), The SBD Steem and Steem power are not representative of your Reputation. Your reputation increases with each vote you get from other users. If you use the Discord chat rooms I am available there should want a more interactive conversation to explain these things, I have included here https://discord.gg/9rE7SmP a link to one of the groups I chat within. It is a small group which is growing and holds contest weekly.