What makes a material able to superconduct

Question

I know most of the physics behind superconductivity and all of that i just dont know exactly what allows a certain material to be able to have a critical temperature

Answer 1

it's to do with the bosonic distribution, unfortunately the space here is far too small to describe, I'd suggest you read Landau's books

Answer 2

i dont think anyone knows the answer for sure

Bardeen-Cooper-Schreiffer (BCS) theory is what i learned.  

you could probably find a lot if you look it up!

another thing to google for info would be 'Cooper pair'