Steem Power is what determines how valuable your upvote is...for instance, my voting weight right now is 2,280 Steem Power...when my voting power is at 100%, a single upvote from me comes to about $0.65 cents USD (US Dollars)...if I leased another 2,280 Steem Power from someone, then my upvote at 100% would be at least $1.30 USD (under the current market prices)...when you upvote a post, comment, or reply, you also receive compensation for content curation...the more SP you have the more curation compensation you can expect when payouts for upvotes come due...I hope this doesn't add to the confusion...