Good question. They both mean exactly same thing, but "thanks" is more informal than "thank you" A really important thing to remember is in English when you want to say thank you for something specific, you always use the preposition for + gerund 1. Thanks for cooking/Thank you for cooking 2. Thanks for buying the food/Thank you for buying the food. 3. Thanks for driving/ Thank you for driving. Hope that helps, Alan

Thanks is less formal than thank you. You can use "thank you" with close friends, associates, and family members, even professional colleagues who know each other well. You can also use it in informal situations, as when a stranger holds the door open for you when your arms are full. "Thank you" can be used if someone gives you a gift in a more formal situation, and any situation where you aren't so close to the other person. More informal: "Thanks" "Thanks a lot." "Thanks a bunch." "Thanks a million." More Formal: "Thank you." "Thank you so much." "I can't thank you enough." "I'd like to thank you from the bottom of my heart."

well basic there is no different but thank you it is more polite way to say it

Thank you = singular Thanks everybody = plural Thank all ya'll = Texan

Thank you is more formal. Thanks is a relatively informal way of saying thank you.