Faith is when you believe without proof. Like you have faith that if you work hard you'll get rewards. It cannot be proven, something could happen and your hard work will go up in smoke but you still work hard because of faith. You have faith that tomorrow the sun will rise and there will be a new day that's why you go to bed early and prepare for the next day. Even though you are not sure tomorrow you'll wake up, you might die in your sleep. That's faith it doesn't require any evidence or proof. Same is faith in God, it doesn't require proofs, you either take the leap of faith or you don't.