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An SMF theme defines the look and feel of your forum. You might call it a skin. The theme sets the order the various elements appear on the page, what color they are, and whether there are any interactive elements included. The very same forum content might look very different when viewed from a different theme. The administrator installs and manages themes from Themes and Layout. For more information on what goes into a theme and how to create or modify a theme, please see Developing Themes