An s4m file extension is related to the SWAT 4 a computer game for Windows. An s4m file stores game map.
S4M file extension - SWAT 4 map
What is s4m file? How to open s4m files?
File type specification:
The s4m file extension is associated with the SWAT 4, an action strategic computer game for Microsoft Windows operating system developed by Sierra On-line.
The s4m file stores game map.