Stamps of the commonwealth countries, generally carry the name of their country in English, although a few include the name in another language as well. The names of many other countries, although in a different language, are still sufficiently similar to their English equivalents, which can be discriminated rather easily. But many are with other inscriptions either in English or in any other language. After identifying the name of the country the other difficulty in Identification that comes before the collector is, to which particular issue or set that particular stamp belongs. As sometimes only some minor variation of designs or perforation, watermark or printing process makes it difficult to differentiate, it is desirable for the collector to take the help of the catalogue.
Stamp catalogue is basically the price list of a dealer.
But now a days it has developed into an invaluable reference book. These catalogues list all countries' authentic postage stamps with their date of issue, denomination, occasion of issue, colour, watermark, perforations and other varieties etc. Stamp catalogues are published by several firms. Among the most famous are Stanley Gibbons of Britain and Scott of United States both in English, Yvert et Tellier in French and Zumstein in German. Besides these general catalogues, many specialized catalogues on individual countries or group of countries are also available.