Changing the ThemeEdit
Like many other programs with a graphical user interface, Blender allows you to customize or modify many aspects of its appearance. A collection of such customizations is called a theme.
Theme controls are found in the User Preferences window. Click LMB on the "Themes" button to activate a drop-down menu which can be used to select different themes. Below this is an "Add" button that can be used to create new themes. If any themes have been added, a "Delete" button will appear, along with other controls to adjust the current theme.
This book presents screen shots using the default theme. If you are new to Blender, you should continue using the default theme as you progress through the book, to avoid confusion.