Difference Between GTK, Metacity, and Emerald Themes


I keep seeing themes as being labelled as metacity or GTK or Emerald. From reading in other places, I gather that Metacity is a window manager and changes the window borders, so what is a GTK theme? Isn't GTK a widget toolkit, used for drawing controls and other interface elements inside the window? and what is Emerald? can somebody please explain in simple noob-to-linux terms?

Best Answer

What you are referring to as a theme is probably a different kind of theme (in light of your comment on Uri's answer).

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Those themes control GTK, Metacity (the Gnome 2 windows manager), Icons, cursors, and sometimes wallpapers all in one. However, they do not control your emerald theme. What you are seeing referred to as a GTK, Metacity, Cursor, or Icon theme is what you get when you click customize.
Each of these controls a different aspect of your interface, and of course, they are all themes in their own right.