The NATO alphabet is an uncanny intersection of being highly memorable and having carefully engineered properties across several dimensions. Whoever designed it did a brilliant job.
It is sticky as hell and surprisingly useful. I do assume that people who know it are ex-military but that isn’t entirely reliable in the US. A lot of other people picked it up, in part because it is so easy to learn by osmosis.
I know it from amateur radio, emergency services, and maritime communications, it's "officially" the International Radiotelephony Spelling Alphabet, shorthanded by some as the NATO Alphabet.
Others may know it by virtue of being fans of, or simply exposed to the Bloodhound Gang.
( FWiW I'm neither in nor from middle North America )
Was really helpfull when making international phone call to services like IRS or sometime good providers. Trying to spell out my french name and long adress or some order number with my strong accent was such a pain until then ^^
It is sticky as hell and surprisingly useful. I do assume that people who know it are ex-military but that isn’t entirely reliable in the US. A lot of other people picked it up, in part because it is so easy to learn by osmosis.