Embossing is an artistic technique which creates a pattern on a material such as paper, metal, fabric, leather, or wood. The pattern can be raised or in relief, depending on how it is embossed. Many consumers interact with embossed items on a regular basis, ranging from embossed book covers to notarized documents. There are a number of ways to emboss something. Some artists emboss by hand, using hand held tools to stamp out a pattern in the material being embossed. This technique will create unique raised designs which cannot be replicated. Embossing of this style is often used for customized art projects, or when ordering an embossing die would seem impractical. The other type of embossing uses a die or roller. Rollers are used for continuous embossing, such as manufacturing leather with a uniform pattern. A die embosses a single piece of material at a time, but it can be used again and again. With both dies and rollers, the pattern to be embossed is carved in reverse, so that when the die is pressed against the material, the desired pattern will show up in the correct form. Typically, a die is designed to be mounted into a press, and is not hand-held. Both dies and rollers also may use heat in order to be more effective.