Proceeds are the money brought in from a transaction or event. The money you make from your lemonade stand are the proceeds from lemonade sales.
You'll often hear something like, all proceeds from this raffle will go to help the Save the Puppies Charity. Proceeds can mean either the gross money earned (all that was brought in) or the net (the money left after expenses). If you are very concerned about where the money you donate to charity goes, this is a good question to ask.