[Q] Whats between phone models? topic

What is the difference between the Samsung Galaxy S5 SM-G900M vs Samsung Galaxy S5 SM-G900F? Im curious as to what makes these devices so different that one rom can't run on both of the devices. On the HTC One forums once you have a GSM based HTC One (Not dual sim) you can pretty much load any of the ROMs on your phone.(Tmobile,A&T,International) but here samsung has so many difference types.