There are two basic types of coffee plant: Arabica, comes from Ethiopia and gives off the best flavour and aroma and Coffea Robusta, comes from Uganda and their beans contain more caffeine.
Coffee has been expanded from Africa to Yemen, after that spread further north to Mecca and Medina. Its characteristic to fight sleepiness, make it very popular among the Sufi, since Koran prohibits the use of alcohol, coffee was considered an exceptionally good substitute.
Coffee approached Europe from Venice, which had strong trade relations with the Arab world in the late 16th century. Today, coffee is the world's second most valuable traded product, behind petroleum.