What is GTK to Gnome shell and unity
What is GTK
At its simplest level - GTK is a graphical toolkit i.e. a series of libraries and a known Application Programming Interface (API) to allow developers to create applications using these predefined libraries of code.
By using such a toolkit, applications have a consistent look and feel - various graphical components will behave in a similar manner
Gnome-Shell & Unity
At their simplest level - Gnome-Shell & Unity are similarly an "application" that uses GTK to give them their look-and-feel.
I'm being highly simplistic - Gnome-Shell & Unity are complex beasts using many programming technologies, window managers etc. They are in-fact many-many individual "applications" pulled together to provide a User Interface you interact with.
I'm counting here scripts of various sorts (python/bash etc), individual applications built in C/C++/Python/Javascript etc etc.
Conclusions
You dont need to do anything to "take advantage" unless you are yourself an aspiring developer - you just need to be aware of the underlying technologies - GTK is just one of many.
Resources:
- How to know my GTK version?
- http://en.wikipedia.org/wiki/GTK
- https://developer.gnome.org/gtk3/3.10/gtk-getting-started.html
- https://wiki.gnome.org/Projects/GnomeShell
- https://unity.ubuntu.com/getinvolved/development/unity/