This site is SO incredibly helpful!! They have awesome teachers who will make understanding even the most complex concepts in Chemistry, Precalculus, Calculus and beyond extremely easy. I am so happy I found it! Also check out their Youtube channel!
Calculus for Beginners and Artists is an online textbook that provides an overview of Calculus in clear, easy to understand language designed for the non-mathematician. Thank you MIT OpenCourseWare for awesome, free resources and classes!!!