Just as there are "classic" cars that never seem to go out of style, there are some classic pieces of software that remain useful long after most of their contemporaries. One of those programs is Xfig, a vector graphics editor hailing from the days of academic Unix workstations. Like the more famous TeX, Xfig hasn't seen significant updates in several years—and for the same reason: it's just about perfect like it is. It is showing its age in the style of its graphical interface, and it does have some fundamental limitations compared to more modern graphics tools, but for the simple technical diagrams it was intended for, it is still hard to beat.
In the dawn of modern computing, there was only text. And the text was good. You can do a lot with text: write equations or sonnets, describe intricate computer subsystems or a fine spring day. But people are visual as well as verbal creatures, and there is simply no substitute for graphical communications.