Debug Script (DOS Debug)
Debug.exe is a debugging program that can serve as an assembler, disassembler or hexadecimal dump program. Debug enables users to inspect memory contents and make changes to memory contents in either assembly, hexadecimal or ASCII. Debug can also selectively run executable file types.
Debug.exe can be used to read DEB debug scripts through the debug < *.DEB command.
A DEB file may contain debug subcommands and assembly language instructions.
Learn more about DEB files:
Wikipedia has an entry on the debug command.
IT Knowledge Exchange has answers for debugging questions.
Tim Fenner explains using Debug Diagnostics to troubleshoot Microsoft IIS issues.
SearchSoftwareQuality.com offers this PDF document on the Art of Debugging.