Understanding Frequency Shift Keying 

Thanks!

(laughs) Actually, a lot of the different FSK modulation schemes have very distinctive sounds -- after a while you can identify many of them just by listening to the pattern of "tones"

(laughs) That's what happens when I go off-script when I'm recording. :) For consistency, I (try to) always refer to digital modulation schemes as modulation order + type. So I would say things like 8PSK, 16APSK, 64QAM, etc. Using this convention, higher order FSK modulation schemes would be 8FSK, 16FSK, etc. No one says "8MPSK" or "64MQAM" - the number indicates they have more than two (M-ary) states, so in my opinion the 'M' is redundant. There is also a something called "minimum shift keying," abbreviated "MSK," so that could ... potentially ... be confusing. [MSK is actually rarely found as "pure MSK" but rather in things like GMSK] But in all honesty, there are lots of people, myself sometimes included, who refer to 16FSK as "16M(F)SK" and that's completely fine. In fact, I would say that "16MSK" is probably a more common abbreviation than "16FSK," so please don't take my offhand comment too seriously :) Thanks for a great question!

Yep. Modems use them aswell.