I am relatively new to Vim. Whenever I start Vim using vim LearnRuby.rb, a dollar sign appears at every line.
Why?
:set nolist
will turn off special characters for the current buffer, such as tabs being presented as ^I and end of line characters showing up as $.
However, if it's doing that consistently when you run vim, you need to look into your .vimrc (or other startup file where applicable) and find out what's doing the set list that causes it.