What are tensors and how do they relate to General Relativity?

[FeynmanMH42]

I know very little about General Relativity, I don't know what a tensor is
and don't know any of the mathematics involved (even though I know
pretty much all of the equations in Special Relativity.)
Could someone please explain tensors to me, or point me to a link that does?
And where can I go to find a mathematical explanation of GR?

 

[pervect]

You may find this heavy going, but you can get some ideas as to the answer to both of your questions at

http://math.ucr.edu/home/baez/gr/gr.html

Do you have calculus yet?