Wallpaper is material which is used to cover and decorate the interior walls of homes, offices, and other buildings; it is one aspect of interior decoration. Wallpapers are usually sold in rolls and are put onto a wall using wallpaper paste.
Wallpapers can come either plain so it can be painted or with patterned graphics. Wallpaper printing techniques include surface printing, gravure printing, silk screen-printing, and rotary printing. Mathematically speaking, there are seventeen basic patterns, described as wallpaper groups, that can be used to tile an infinite plane. All manufactured wallpaper patterns are based on these groups. A single pattern can be issued in several different colorways.

Use
Like paint, wallpaper requires proper surface preparation before application. Additionally, wallpaper is not suitable for all areas. For example, bathroom wallpaper may deteriorate rapidly due to excessive steam. Proper preparation includes the repair of any defects in the drywall or plaster and the removal of loose material or old adhesives.

Removal
Interior decorating styles change over time, and eventually a person may wish to remove that once lovely wallpaper.

Perforation
Most of the methods of wallpaper removal can be aided by mechanically perforating or scoring old wallpaper with a tool called a Paper Tiger, which looks like a puck with a wheel of sharp teeth. Rolling this tool on the wall in a clockwise or counterclockwise motion effectively creates tiny holes in the surface of wallpaper, but leaves the drywall undamaged.
The paper tiger is used for removal of non-peelable vinyl papers. Peelable vinyls are 2 layer papers, the top layer peeling off to leave a paper backing, which, being porous, is removed by just wetting it.
Perforation is followed by the application of either water, a chemical wallpaper stripper or steam to dissolve the underlying wallpaper paste.

Water
The simplest removal option is to brush the paper with water. Water soaks through the paper and saturates the glue, allowing the paper to be peeled off.
This does not work well with nonpeelable vinyls, as vinyl is not porous. Nevertheless it is still effective on many modern papers.......

Chemical Wallpaper Stripper
Chemical wallpaper stripper can be purchased at most paint or home improvement stores. It is mixed with warm water or a mixture of warm water and vinegar, then sprayed onto wall surfaces. Several applications may be required to saturate the existing wallpaper. Perforation can aid in the absorption of the mixture and lead to faster removal. After the mixture has dissolved the wallpaper paste, the wallpaper can be removed easily by pulling at the edges and with the aid of a putty or drywall knife.

Steam
Another method of removal is to apply steam to wallpaper in order to dissolve the wallpaper paste. A wallpaper steamer consists of a reservoir of water, an electric heating element, and a hose to direct the steam at the wallpaper. The steam dissolves the wallpaper paste, allowing the wallpaper to be peeled off. However, care must be taken to prevent damage to the drywall underneath. Sometimes steaming can lead to the crumbling of underlying drywall or plaster, leaving an uneven surface to be repaired.