What is the relation between GTK, GTK+ and GTK2?

Question

I\'m confused by the GTK terminology. According to Wikipedia, there seem to be bindings to GTK+ that are called GTK (GtkAda) and GTK2 (gtk2hs, Gtk2-Perl).

Could someone

Answer 1

GTK is the library for creating GUI-s for Linux / GNU. It has several versions (I think the latest is version 3).

In order for other programming languages to use it (other than C), there have to exist libraries that can bind GTK to that particular language.

PHP-GTK means that there's a library binding GTK to PHP enabling PHP to create apps that can be displayed in a nice interface. It supports, however, only up to version 2.2 of the GTK. Same goes for other languages, they have a prefix / suffix and (GtkAda for example) those libraries also tell you up to what version they support GTK (since you might want to try newer GTK functions that aren't available in the library binding GTK to your language).