That’s because files on the Mac can often be opened with multiple apps, hence the Open With… context menu selection in the Finder. Select a file, right-click, and select the Open With… menu. What happens next is scary and useful.
Open With What?
The Open With contextual menu (what happens when you right-click on a file) gives you options that make sense; sometimes, but not always.
Open With lets the Mac figure out which apps can open a particular document (ostensibly the one you selected in the Finder).
The problem lies in how many different apps can be used to open and edit a document. Some apps have been deleted from the Mac but still show up in the Open With menu.
Worse, plenty of apps in the menu may not match the document you want to open. That brings me to Clean Open With, a Mac utility– free, of course– that gets rid of what you don’t need in the Open With menu.
That includes apps that are no longer on your Mac, or the crazy duplicates which seem to appear sporadically.
Here’s an example.
Notice the two versions of Safari in the Open With menu? For whatever reason OS X doesn’t always clean up after itself. Clean Open With rids the Open With menu of apps that are not on your Mac.
Because Clean Open With is a script utility it might look a little ugly while it’s doing the deed to wayward apps in the Open Menu menu. Fear not. Terminal is only ugly if you don’t know how to use it.