a) Xerox Alto predated by at least 10 years.
b) I saw split windows and alternating windows over SDLC terminals on IBM mainframes in the
c) Remember that for many years, particularly the boom computing years of the '60s and '70s,
it was *impossible* to patent software. The USPTO wouldn't take applications, and decisions
on systems said things like "algorithms are laws of nature". That's why it became so
ridiculous that they went all the way to patenting "business methods" like remembering what a
customer likes and suggesting similar items (gee, haven't shopkeepers been doing that forever?
not to mention moms?)