Multitasking is so obvious today we don't even notice it. Some exceptions, such us iPad, remind us of the days when this was not possible. A few months ago ./ had an article about a Blit Terminal - claimed as a first multitasking GUI. Let's name a few GUIs that supported multitasking in that era and their evolution:
- 1979 (1980) OS9 (included a GUI on some platforms like Tandy Color Computer)
- 1981 Xerox Star
- 1982 Blit Terminal (allowed usage of many applications from the server at once on the terminal)
- 1983 Apple Lisa
- 1984 X windows (similar to Bliz it allowed multiple applications to run on the server and showing them on the client terminal)
- 1984 Apple Machintosh
- 1984 IBM TopView (multitasking for DOS)
- 1985 Atari TOS/GEM (kind of multitasking via special accessories)
- 1985 Amiga
- 1985 Deskqview multitasking for DOS applications
- 1985-87 Windows 1.0 (tiled windows) - 2.1 (real multitasking)
- 1986 (1989 first public release) NextStep (object-oriented, multitasking OS)
- 1988 OS/2 1.1 (similar to Windows 2.1)
I see this as 3 different development branches: (1) development of standalone multitasking GUIs for personal computers, (2) development of server-terminal GUIs and (3) bringing some "GUI" multitasking functionality to CL interfaces.
None the less, it is impressive what these systems were capable of, given the time and hardware available, while still trying to lower the prices for the masses.