The objects which you can see in the sky are described in a variety of astronomical catalogs which overlap to some extent. Many bright stars have proper names like Albireo or Betelgeuse, which mostly come from the Arabic. To avoid confusion, the brightest stars in each constellation were given a Greek letter, which is complemented by the Latin abbreviation of the constellation name – α Ori is, for example, Betelgeuse in Orion. Often the constellation name is also written out – α Orionis or Alpha Orionis. The system was introduced in 1603 by Johann Bayer in the star atlas „Uranometria“.
In order to describe more stars, John Flamsteed simply numbered the stars of each constellation in the 17th Century. Betelgeuse therefore also carries the designation 58 Orionis. Again, this approach was not sufficient for modern, extensive star charts. But other catalogs such as the Bonner Durchmusterung or the number in the SAO catalog or in the Hubble Guide Star Catalogue are rather uninteresting for amateur astronomers.
Deep-sky objects are listed in a variety of catalogs. The Messier catalog goes back to the French comet hunter Charles Messier, who cataloged 103 „nebulae“ in the 18th Century, which disturbed him in his hunt for comets. The catalog was later expanded somewhat and lists many of the finest deep-sky objects. M 31 is, for example, the Andromeda galaxy.
Much more extensive is the New General Catalogue of Nebulae and Clusters of Stars, published by JLE Dreyer in 1888. It contains 7840 entries. NGC 224, for example, is the Andromeda galaxy M 31. The catalog was later extended by two „Index Catalogues“. Its objects are abbreviated with IC and are usually unobservable in binoculars.
In addition, there are a number of special catalogs, which are usually limited to an object class. Some of these catalogs contain hundreds of entries, others only one. For open clusters there are, for example, the catalogs of Collinder (471 objects, abbreviated as Cr, for example the „Coat Hanger“ Cr 399), Trümpler (English: Trumpler, 334 objects, abbreviated Tr) and Melotte (abbreviated Mel, for example the Coma Star Cluster Mel 111). These catalogs were usually composed at the beginning of the 20th Century.
For binoculars, one list is especially interesting, which mainly contains asterism (random star patterns) for binoculars and was presented by Phillip S. Harrington in 1990. It contains 12 items – Hrr 1 is, for example, the „engagement ring“ near the North Star. The list was later expanded to the STAR (Small Telescope Asterism Roster) with 29 entries.
For dark nebulae, the catalog of Edward E. Barnard is an interesting source. Published in 1927, it contains a list of 370 dark nebulae. B72 is for example the snake nebula in Ophiuchus. Lynds Dark Nebulae Catalogue of 1962 is even more extensive – it includes 1802 entries. LDN 906 in Cygnus, for example, is the “Northern Coal Sack“, the 2.5° wide end of the Great Rift of the Milky Way.