nano is a GPL-licensed clone of pico, which in turn was originally conceived as the integrated message editor in PINE, the popular UNIX e-mail client first rele

nano is a GPL-licensed clone of pico, which in turn was originally conceived as the integrated message editor in PINE, the popular UNIX e-mail client first released in 1989. If you look at the overall interface of PINE you will recognize that it is consistent with pico/nano, but other than that there really wasn't much consistency in terms of keyboard commands between apps in 1989. More importantly, while for instance ^S for "save" might seem more natural than ^O for "writeOut", remember that dumb terminals over slow lines were still very much a thing in 1989 and ^S was already used as a terminal control code for XOFF (software flow control) -- which is why nano throws that "XOFF ignored, mumble mumble" message when it catches ^S.