Hello, I know all my algebra, trig, and I'm still fine tuning calculus and I've solved ODEs using the Laplace transform. Now, my question is... what else must I know to study Tensor calculus/Tensor Analysis? I really want to know so that I have a true understanding of relativity(the famous einstein field equations especially) I am a high school senior, in AP Calculus, and I'm looking to the future. What classes will I need to take in college to truly understand enough so that I don't get frustrated when I try to deal with vector analysis/calculus and tensors? I'm reading about it, but having trouble grasping some of it, something is missing in my background most certainly. Can anybody tell me what I need to know to understand these concepts?