Could someone explain to me how Steemit rewards work?

Hi Everyone

 I am trying to understand how steemit rewards work . I post, vote and resteem and nothing is entering my account. I looked the wallets of people with way more traffic and I see nothing. I did some research, some articles say it takes 12 hrs to get paid, others say 1 week. I am not sure if this works at all.

Could someone explain to me very simply how this works.

Thx