When you make an ACCDE file (E=Encrypted or Execute Only, depending who you ask) then Access compiles the design and VB source into a pseudo-machine language so the user can't get at it.

Just to add to Richards comment the ACCDE file is not a true Executable (.exe) file.  You still have to have either a full copy of Access or the runtime addition in order to use the file.

It doesn't make it a stand alone program that you can distribute.

Access Runtime