There are two main species of coffee beans in the world, Coffee Arabica, and Coffee Robusta. More than three-quarters of the beans that are sold in the world today are Coffea Arabica, the majority of the remainding bulk are Coffea Robusta also known as Coffea Canephora.
These beans are of a lower grade than Arabica, and are typically grown at lower elevations. They are easier to grow and maintain, and they are also more disease resistant and produce a higher yield. Robusta beans have more of an astringent flavor and contain a higher amount of caffeine.
These are the higher quality beans and are referred to as gourmet coffee. They have half the amount of caffeine as Robusta and have more pleasing flavours and aromatic properties. Most Arabica bean varieties are name after their country or region in which they are found, or originated from.
Other bean species include: benghalensis, Bengal coffee; Coffea congensis, Congo coffee; Coffea liberica, Liberian coffee; Coffea stenophylla, Sierra Leonian coffee; Coffea excelsia, another Liberian coffee; Coffea bonnieri; Coffea gallienii; and Coffea mogeneti, however these beans are non-existent in the export market.