title: nodejs is already the newest version but "node -v" doesn't give a response
body: <p>This is really confusing me. If I type "node -v" into the command line, there is no response - it just gives me the <code>$</code> prompt again. Trying to install node with <code>sudo npm install nodejs</code> gives the response <code>nodejs is already the newest version</code>.</p>
  
  <p>How can I debug this to find out what's going on?</p>