Localization best practices

Hi i have a question regarding best practices when using lolcalization.

Should i use both Namestapce and Key?

So far i used only Namespace, but i left Key to be randomly generated. Is this ok?
So i have something like this
(Menu.ButtonOk.Text, 073DFEEF47A1D3C089A19B98D4126765)
With using Key to get something like this
(MenuButtonOk, ButtonText) ?