Chuck Forsberg has died – author of Zmodem
In the pre-internet-for-everybody days (and even quite a while afterwards) zmodem and other file transfer protocols were pretty much the only way short of mailing floppy discs to get a file from one place to another, and there wasn't a terminal package or a BBS system that did not support it. Even today plenty of terminal programs will happily respond to the download initiation sequence.