This package is an Emacs minor mode and allows you to edit one occurrence of some text in a buffer (possibly narrowed) or region, and simultaneously have other occurrences edited in the same way.

You can also use Iedit mode as a quick way to temporarily show only the buffer lines that match the current text being edited. This gives you the effect of a temporary `keep-lines' or `occur'. To get this effect, hit C-' when in Iedit mode - it toggles hiding non-matching lines.