Charity or philanthropy is the act or gift of your time, money, property, or other helpful resource to someone else who needs it but can't get it in another legal or reasonable way.
Charity is the idea that all of us humans living on our planet have a responsibility to care for each other, to lend a hand when needed, and to act for the common good. It is the idea that when we act for the common good to help others, we are also helping ourselves. Who benefits from AIDS research funds? Just the victims? No, their families and friends receive the benefit as well. So do their customers wherever they work and so do the companies that they patronize.
Should one of those people who lives because of that same research later design a powerful solar cell based on research from a charitable grant, then we could power our homes via that new technology. Who benefits from charity? More people than you will ever realize.