A pef file extension is related to the Macintosh Preferred Executable Format.
There is one other file type using
the PEF file extension!
.pef - Pentax Digital Camera Raw Image Format
PEF file extension - Macintosh Preferred Executable Format
What is pef file? How to open pef files?
File type specification:
The pef file extension is associated with the Preferred Executable Format, an executable file format used by applications written for Macintosh computers with PowerPC processors.
Obsolete file format not used in Mac OS X (macOS).
This pef file type entry was marked as obsolete and no longer supported file format.
This type of file is no longer actively used and is most likely obsolete. This is typically the case for system files in old operating systems, file types from long discontinued software, or previous versions of certain file types (like documents, projects etc.) that were replaced in higher versions of their original programs.