hello,,
i am a noob as well,, welcome to the world of Android! Root in a method use to take the power out of the hands of the provider,, and putting you at full (super user) control of your device! This will enable you to load custom rom"s,, remove pre-installed apps, or Bloat ware, i.e sprint apps like nascar, stocks etc.. if you are like me,, they are things that i will never use,, they are just taking up space in my phone! Check out this link! It will further more explain just what root is and how to obtain it!
YouTube - What is "Root"?: How To Root Your Sprint Evo 4G (Part 1 of 3)
Ps,, if you choose to root your phone,, please READ, READ AND DO SOME MORE READING! you can never be to informed! And make sure that the methods that you use is a FULL ROOT W/NAND UNLOCKING!