title: What's the most appropriate HTTP status code for an "item not found" error page
body: <p>I'm curious what's the most appropriate HTTP status code for an "item does not exist" page.</p>
  
  <p>If the page itself doesn't exist, I'll obviously use 404. However, one of my pages has a <code>userid</code> argument (it's an "edit user" page) and in case no user with the given user ID exists I'm displaying an error page, but I'd also like to send a 4xx status header (since "200 OK" doesn't really fit).</p>
  
  <p>I guess 404 would be ok since it's "not found" and not "file not found", but I wonder if there's a better code for this case.</p>