An MDE is an Access file that has been fully compiled and the source code stripped
out. This renders all Reports, Forms, and Modules non-editable and there is no way
to view any of the code. Other than that it "runs" pretty much the same as the MDB
it was created from. It still needs MS Access to operate. It's just a bit smaller,
faster, and has a bit of security because code access has been removed.
Because no module-based items can be edited there are certain things that cannot be
done in an MDE like change references for example.