It's Lua and Perl; all caps aren't necessary.
http://www.lua.org/about.html under "What's in a name?"
and
http://en.wikipedia.org/wiki/Perl under "Name".
It might be petty to point this out, but it's simply annoying to see.
As to the title of the thread, I prefer Perl for some tasks and Lua others.
In my opinion, Perl is better for general administrative tasks and Lua for embedded scripting languages.