I want to learn how to C

Hello,
I'm not a professional programmer, but I have learned how to Python in Codecademy, and I know there's still a lot to go. I'm trying to improve myself with python challenges and projects found on teh webz and etc. What I'd like to know is: given this limited background, how hard would it be to learn how to C ? And how could I do it?

thanks

Read The C Programming Language and never post here again