Coffee is a member of the large Rubiaceae family, comprising the genus Coffea, first described by C. Linnaeus in 1717. The two main species cultivated commercially are Coffea arabica and Coffea canephora, which includes the extremely widespread Robusta variety. Arabica, the oldest known and most widespread species, originated not in Arabia, as its name suggests, but from Ethiopia, where it grew in immense stands on high plateaus. Canephora was discovered in Africa towards the end of the 18th Century. Together, these two species account for 99% of the world's coffee.

Coffee was originally brewed from raw, green beans to yield a tea-like beverage. Arabians first began roasting and grinding coffee in the late 13th Century. As the brew spread in popularity from Constantinople to Venice, then Vienna, and the European capitals, it was condemned by religious leaders of all faiths for its supposed intoxicating effects. Initially, coffee was sold by pharmacists, and then in cafes, which became notorious as hangouts for intellectuals and artists. Today, despite possessing virtually no nutritional or health benefits of any kind, coffee is the most popular beverage in the world, with more than 500 billion cups consumed each year.

The word "coffee" is derived from an Arab word, qahwa, which means literally: "that which prevents sleep." The Italian word capuccino means "little hood" and originally referred to the Capuchin friars, a Roman Catholic order of monks. Cappucino coffee reminded 14th Century coffee drinkers of these friars' brown robes with pointed hoods. Taking a bath in coffee grounds fermented with pineapple pulp is a traditional Japanese therapy for reducing wrinkles. In 1734, Johann Sebastian Bach wrote an opera titled The Coffee Cantata, in which the heroine sings: "coffee is more delicious than a thousand kisses, and sweeter than muscatel wine”.

The first documented coffee plantation in Hawaii occurred in 1813, unsuccessfully. In 1825, coffee was cultivated in Manoa Valley at the behest of the governor, rapidly spreading to all the isles. As the sugar industry prospered, many coffee farms were converted to sugarcane. By 1920, virually all of the commercially grown coffee in the Hawaiian Islands was cultivated in Kona.

Coffee beans are the seeds of a fruit, picked when red, and acquire their familiar brown color and enticing aroma only upon roasting. Of the two predominant species, Arabica beans are of superior quality, producing the finest flavors when grown at high altitudes in semitropical climates. Robusta beans require less care and thrive in low altitudes, and have twice the caffeine. Most commercial coffee is Robusta, often with a small percentage of arabica beans added for flavor. In contrast, almost all gourmet coffee is Arabica.

Coffee is processed by either of two methods: the dry ("natural") method or the wet ("washed") method. In the dry method, coffee berries are sun-dried for several weeks on elevated racks or screens, which are covered at night to prevent spoilage. The dried berries are then husked prior to grading and roasting. In the wet method, the outer pulp is removed by machine. The beans are then placed in large fermentation vats. Finally, the beans are washed and dried, either in the sun or in drying machines.

Most gourmet coffee, including Kona coffee, is processed by the wet method. The processed beans are sorted through sieves or by machine, according to size and weight. Imperfect beans or foreign matter are removed by hand. The beans must be roasted before the coffee can be brewed. In general, the darker the roast, the more developed the flavors and aromas. However, over-roasting results in a bitter, acrid brew; so skill in roasting is essential to the art of coffee processing.

Hawaii currently produces 8.5 million pounds of coffee per year. The total acreage devoted to coffee planting is estimated at 7,600 acres, of which 93% is located in Kona. Conducive temperatures and a nearly optimal distribution of rainfall favor the cultivation of coffee in the Kona Coffee Belt. The soil, though of variable depth, is rich in organic matter, due, in part, to its volcanic origin.

Coffee harvesting occurs throughout the year in Hawaii. The main harvest begins in late summer and extends to the early part of the following year. Kona farmers account for 96% of the total coffee production of Hawaii Island, with a harvest of 3.3 million pounds.