This deserves to be higher. It spawned GTK, which spawned Gnome and so on. In this way, it is one of the most influential open source software programs around.

This deserves to be higher. It spawned GTK, which spawned Gnome and so on. In this way, it is one of the most influential open source software programs around. I recall also that in it's youth, it showed what is possible, it staked out a future. There were not many as advanced GUI programs around like it then, but xv was of course the go-to program in the graphics category.