The authors of GTK+ are:
GTK+ is a small and efficient widget set designed with the general look and feel of Motif. In reality, it looks much better than Motif. It contains common widgets and some more complex widgets such as a file selection, and color selection widgets.
GTK+ provides some unique features. (At least, I know of no other widget library which provides them). For example, a button does not contain a label, it contains a child widget, which in most instances will be a label. However, the child widget can also be a pixmap, image or any combination possible the programmer desires. This flexibility is adhered to throughout the library.
Peter Mattis informed the gtk mailing list that:
"I originally wrote gtk which included the three libraries, libglib, libgdk and libgtk. It featured a flat widget hierarchy. That is, you couldn't derive a new widget from an existing one. And it contained a more standard callback mechanism instead of the signal mechanism now present in gtk+. The + was added to distinguish between the original version of gtk and the new version. You can think of it as being an enhancement to the original gtk that adds object oriented features."
Peter Mattis informed the gtk mailing list that:
"I think the last time Spencer and I talked about it we decided on GTK = Gimp ToolKit. But I don't know for sure. Its definately not GNU, though."
In the GTK+ distribution's doc/ directory you will find the reference material for both GTK and GDK, this FAQ and the GTK Tutorial.
In addition, you can find links to HTML versions of these documents by going to http://www.gtk.org/.
The Tutorial and FAQ can also be found at http://www.geocities.com/ResearchTriangle/Lab/4299/.
There are two mailing lists:
A searchable archive of the mailing list can be found at http://archive.redhat.com/gtk-list
No, everyone's just busy coding.
First, make sure your question isn't answered in the documentation, this FAQ or the tutorial. Done that? You're sure you've done that, right? In that case, the best place to post questions is to the GTK+ mailing list.
Bug reports should be sent to the GTK+ mailing list.
Some applications which use GTK+ are:
In addition to the above, the GNOME project ( http://www.gnome.org) is using GTK+ to build a free desktop for Linux. Many more programs can be found there.
Ask on gtk-list for suggestions. There are at least four IRC clients already under development.