For physics and math classes, it would be very useful to be able to type out equations with symbols and such. I believe that LaTeX allows you to do this, but I am not sure. So, what is LaTeX exactly and what is the best way to get started?
LaTeX is a typesetting language. It alows you to use write equations and many other things.
A good place to start learning it would be this website: http://latex101.wikispaces.com/Syllabus