title: Vim "yank" does not seem to work
body: <p>I'm fairly new to Vim. Tonight, I learned about the "yank" command, but when I try to use it in MacVim, it doesn't do anything. Neither <code>Y</code> nor <code>y{motion}</code> do anything. I tried with a default <code>.vimrc</code> to rule out any weird config issues.</p>
  
  <p>Google-fu is failing me. This feels like a noobie issue. Am I missing something obvious?</p>