The .ad file extension is related to the UNIX operating system and used for its application default resource files.
AD file extension - UNIX application default resource file
What is ad file? How to open ad files?
File type specification:
The AD file extension is associated with the UNIX operating system for various computer platforms and other computing devices developed by AT&T. The .ad file contains application default resource data.
The default software associated to open ad file:
Company or developer:
The Open Group
A multi-tasking operating system for various platforms, the first version of UNIX was released in 1969. It is developed by AT&T as well as various commercial vendors, universities and non-profit organizations. Traditional Original Unix systems have characteristics of Version 7 Unix or UNIX System V. Unix Specification have Mac OS X, Mac OS X Server, Solaris, AIX, HP/UX, z/OS etc. Other systems, such as Linux and BSD are called Unix-like or Unix system-like.
List of recommended software applications associated to the .ad file extension
Recommended software programs are sorted by OS platform (Windows, macOS, Linux, iOS, Android etc.)
and possible program actions that can be done with the file: like open ad file, edit ad file, convert ad file, view ad file, play ad file etc. (if exist software for corresponding action in File-Extensions.org's database).
Unspecified and all other actions for computer programs working with ad file - UNIX application default resource file
Click on the software link for more information about Unix. Unix uses ad file type for its internal purposes and/or also by different way than common edit or open file actions (eg. to install/execute/support an application itself, to store application or user data, configure program etc.).