hi all, as shows on the subject, it is a really really beginner
question.

i was trying to do the "hello world!" on my mac (v10.4 with ruby
1.8.2) in text editor,
but i could not save it with a .rb extension.

can someone please point out what i did wrong ?
thz in advance.

p.s. is there any simple free editor program  for beginner that will
help me to learn ruby better?