Hi @sapwood,

Who pays the money when you hit the upvote button??

When you upvote someone’s post - that value is not being withdrawn from your personal account. You’re not giving anyone anything from your personal savings or STEEM Power. Instead, you’re vote is actually tapping into a brand new pool of STEEM. There’s a fresh batch of STEEM produced every day, and it’s called the daily rewards pool. The rewards pool is an amount of STEEM generated every day from inflation. This daily STEEM represents the pool from which your vote takes a certain amount and distributes it to where you’ve directed.

When you hit the upvote button you are informing the STEEM Blockchain, “this is where I want X amount of the daily rewards pool to go.” The amount that you’re able to direct is dependent on the amount of STEEM Power you have. So the more SP you have, the more of the daily rewards pool you can direct to posts you like! (Your vote is not affected by liquid STEEM or SBD).

What happens if someone hits the downvote button, I mean where does the reward go after downvoting??

When someone hit the downvote that means the person felt more beneficial to the other active posts in the platform. And rewards goes back to the reward pool.

What is the different between 50/50 reward and 100% reward? Will you get the same currencies in both?

When you publish your post by default set 50% SBD/50% SP , Which means, you will be receiving your rewards in 50 percent Steem Power and 50 percent Steem Dollar. I believe that it was set that way so that the rewards will not be all liquid and also to increase the Steem Power of an author.

When you choose the Power Up 100%, means that all your author rewards will be in Steem Power. If you wish to receive purely Steem Power whether to increase the value of your votes faster or simply wanting it to be all in Steem form, this is a good option to choose for anyone. Steem Power as described in Steemit page is: "Influence tokens which give you more control over post payouts and allow you to earn on curation rewards."

this is my understanding of "voting & curation".

Thank you