My TI-84 calculator update?

How am I suppose to update my ti-84 graphing calculator? I don't have a CD or the calculator cable that it comes with but im not sure if I need them...I just really want to get math print and possibly other stuff for my calculator and get to version 2.55 its in version 2.40 right now...my friend is updating hers and getting Area formulas, periodic table, polynomial root finder and equation solver, probability simulation...are you able to explain to me what that stuff is and if I need it or if its useful? And also how to get the apps