The name of the GUI
implemented in Sun's OpenWindows
system. Introduced around 1990; still available.
Open Look is functional, but it looks unpolished and clumsy; try the file manager, filemgr, for an example.
Some of this is accounted for by the fact that it had to be ported from NeWS to X; rounded menu items for instance don't render as easily on X as on NeWS.
It also some annoying deficiencies.
For example, Open Look applications tend to disallow typing full path names to files in one place, instead you must browse to the directory, then type the filename. This means, for example, that when you want to navigate from your home directory to /tmp, or vice versa, the app will insist on listing the contents of / and /home, which is useless and costly. Even if Open Look didn't actually impose this broken behaviour - can anyone be bothered to check? - it propagated it in practice.
(Note: some websearches on Open Look can probably improve this writeup a lot - it's just a first start. Please /msg me with suggestions.)