Styles are define in XAML and are used to set dependency properties of WPF Controls. Styles can be either named or target a type. If you want your Style to be applied to e.g. a Button to give it a special appearance in your whole application you should let your Style target the type ‘Button’. WPF then will apply your style to all Controls of type ‘Button’ in your application as long as your Style is inside the scope of the respective buttons. Styles are also useful to add animations to dependency properties.