Grub2/Troubleshooting page possible error

I can't find the best method to communicate this, so try 'ask a question way' (before to try 'report a bug way').

In this page: https://help.ubuntu.com/community/Grub2/Troubleshooting#Overview i can see:
[QUOTE]1.grub> prompt: GRUB 2 loaded modules but was unable to find the grub.cfg file.

2.grub rescue> prompt: GRUB 2 failed to find its grub folder, or failed to load the normal module.

3.grub>: - The grub prompt on a blank screen.

    GRUB 2 has found the boot information but has been either unable to locate or unable to use an existing GRUB 2 configuration file (usually grub.cfg).

4.grub rescue>: - The rescue mode.

    GRUB 2 is unable to find the grub folder or its contents are missing/corrupted. The grub folder contains the GRUB 2 menu, modules and stored environmental data. [/QUOTE]

I'm not sure about differences between 1 and 3, and between 2 and 4.
I think it's possible this is an error and is confusing for readers.

If someone thinks it's worth to fix it and knows how to do it... thanks.
(I speak spanish or italian a lot better than english, so sorry for possible messing.)