Wallpaper is used in interior decoration to cover the interior walls of domestic and public buildings. It is usually sold in rolls and is applied onto a wall using wallpaper paste. Wallpapers can come plain as "lining paper" to help cover uneven surfaces and minor wall defects, "textured", plain with a regular repeating pattern design, or with a single non-repeating large design carried over a set of sheets.
The smallest wallpaper rectangle that can be tiled to form the whole pattern is known as the pattern repeat. Wallpaper printing techniques include surface printing, rotogravure, screen-printing, rotary printing press, and digital printing.