sheets typically include additional artwork or information printed on the selvage, the border surrounding the stamps. Sometimes the stamps make up a greater picture. Some countries, and some issues, are produced as individual stamps as well as sheets. Stamp collecting Stamp collecting is a hobby. Collecting is not the same as philately, which is defined as the study of stamps. The creation of a valuable or comprehensive collection, however, may require some philatelic knowledge. Stamp collectors are an important source of revenue for some small countries that create limited runs of elaborate stamps designed mainly to be bought by stamp collectors. The stamps produced by these countries may far exceed their postal needs. Hundreds of countries, each producing scores of different stamps each year, resulted in 400,000 different types of stamps in existence by 2000. Annual world output averages about 10,000 types. Some countries authorize the production of postage stamps that have no postal use, but are intended instead solely for collectors. Other countries issue large numbers of low denomination stamps that are bundled together in starter packs for new collectors. Official reprints are often printed by companies who have purchased or contracted for those rights and such reprints see no postal use. All of these stamps are often found "canceled to order", meaning they are postmarked without ever having passed through the postal system. Most national post offices produce stamps that would not be produced if there were no collectors, some to a far more prolific degree than others. Sales of stamps to collectors who do not use them for mailing can result in large profits. Examples of excessive issues have been the stamps produced by Nicholas F. Seebeck and stamps produced for the component states of the United Arab Emirates. Seebeck operated in the 1890s as an agent of Hamilton Bank Note Company. He approached Latin American countries with an offer to produce their entire postage stamp needs for free. In return. he would have exclusive rights to market stamps to collectors. Each year a new issue would be produced, but would expire at the end of the year. This assured Seebeck of a continuing supply of remainders. In the 1960s, printers such as the Barody Stamp Company contracted to produce stamps for the separate Emirates and other countries. The sparse population of the desert states made it wholly unlikely that many of these stamps would ever be