I would like to give you a little inforamtion about using thanks and thank you :
In the country of english , I mean britain they use thanks to those people who know.
But they use thank you to those people who dont know.
In the country of english , I mean britain they use thanks to those people who know.
But they use thank you to those people who dont know.
May God help you learning and teaching english as you hope.
Thanks alot for the post & as you said (thanks) is casual while (thank you) is more formal