The “Open With” menu of your Mac, that you get when you right-click (or control-click) a file in the Finder window, may become extremely cluttered with time containing duplicate entries or even stale ones pointing to applications that are no longer installed on your Apple computer. Here’s an example:

If the “Open With” menu of your Mac is also messy and filled with applications that you no longer use, you can easily clean it up by rebuilding the Launch Services database with a simple Terminal command.

Full article here:
Clean-up the “Open With” Menu of your Mac (Digital Inspiration)