There are two types of coffee bean: Arabica and Robusta.

Arabica is the more expensive of the beans mainly because of the higher altitude it grows and therefore is harder to harvest. It is grown at around heights of 3,000 feet above sea level.  Arabica beans have generally less caffeine, are less acidic, and have more flavour and aroma.

Arabica is used in a higher concentration for a good espresso drink, or non-milk coffee for its strength and taste.

Robusta is grown at a lower level and is far more hardy.  It is used to help preserve the coffee taste in a milk-based drink such as a latte or cappuccino.  It is grown at around 2,000 feet above sea level.  Robusta is used more in instant coffee and filter coffee to keep the roasters’ costs down to a minimum.  

It has twice the caffeine of Arabica and much less flavour.

Coffee is sold as either 100% Arabica or a blend of the two beans.  When coffee is blended to an individual blend, the roaster can manipulate the flavour of the blend by adjusting the percentages of Arabica and Robusta beans used.