Some of the old Unix GUI interfaces had a literal pin image on the corner of the top bar of each window. Clicking on it did exactly what you'd expect - pinned t

Some of the old Unix GUI interfaces had a literal pin image on the corner of the top bar of each window. Clicking on it did exactly what you'd expect - pinned the window at this particular size/location and didn't let anything else overlap to cover it unless it was pinned that way. (they could "underlap" though).