How to open the language folder in Minecraft?

So, I want to change the name of an object in minecraft 1.7 and higher, but I can't find the language folder in the minecraft.jar.
What exactly is the folder called or at least its location?
I'm running Windows.

Guest

I have seen that you can do this with a resource pack. I'm not sure how but i have seen it done before. I know that they have hidden things like this in minecraft.jar because they say to do it with resource packs.