TAXES

I'll soon be doing taxes, but I don't know why. I don't understand how the whole income tax system works. So I just learned how I'm supposed to claim my tips at work [i'm a waiter]. The more I claim, the more gets taken out of my check. But I get the money back when I do my taxes. I'm lead to believe that the money that gets taken out goes to the government to be spread into different government programs to help the people and communities out. But if I get the money back, where is the money coming from when i get it back? If the money was given out the people, then how am I possibly getting it back? I mean I'm really confused. I think I'm going to google this shit. no joke.