Most Customers with an interest or passion in home décor, and more particularly, the picture framing and display of art on paper, such as photos, prints, posters and the like, will probably already know what is a window mat  (or window mount  or passé-partout as it is known in Europe)  when researching window mat designs . However for those who may not be fine art aficionados, a window mat is paper or cardboard edge one often sees around many of the nicer photos or images. It creates a separate field of colour, definition and light, between the picture frame and the art itself. More prosaically, it keeps the glass off and away from touching the art ...