The mnemonic of a mythical ascii control character (End Of User) that would make an asr-33 teletype explode on receipt. This construction parodies the numerous obscure delimiter and control characters left in ASCII from the days when it was associated more with wire-service teletypes than computers (e.g. fs, gs, rs, us, em, sub, etx, and especially eot). It is worth remembering that ASR-33s were big, noisy mechanical beasts with a lot of clattering parts; the notion that one might explode was nowhere near as ridiculous as it might seem to someone sitting in front of a tube or flatscreen today.

[jargon file]