Definition of "Rotate case"

[Sveinn_i_Felli]

Hi,

In officecfg/registry/data/org/openoffice/Office/UI.po there is:

#: GenericCommands.xcu#..GenericCommands.UserInterface.Commands..uno_ChangeCaseRotateCase.Label.value.text
msgid "Rotate case (Title Case, UPPERCASE, lowercase)"
msgstr ""

What does this actually do ?
Is there a definition somewhere ?

The surrounding options are understandable due to their capitalization, but here a comment might come handy.

Best regards,

Sveinn í Felli