There are really only two species of coffee plants which beans are harvested from, the Coffea Arabica which produces the wonderful arabica bean and the Coffea Canephora which produces the robusta bean. The coffee been itself is the pit or stone of the coffea plant’s cherry.
Arabica beans
Due to being hard to grow, susceptible to pests and disease and needing several years to mature before it will produce cherries, Arabica coffee beans are more expensive.
The most commonly associated countries for growing aribica beans are in South America; Columbia and Brazil, However Africa also produces quite a large volume of these beans.
Robustas beans
The Coffea Cenephora plant is very hardy and can produce large volumes of cherries at a very early age. The beans are highly charged with caffine however they are harsher and a little more bitter.
Robusta beans are cheap and mostly used in supermarket brands, instant coffee and cheap coffee grounds are usually made from this bean.
In Summery
Robusta – Cheap, highly caffeinated (2x the amount of Arabica), strong flavour, bitter taste however good quality robusta can be used for espresso. Typically used in Italian blend and instant coffee.
Arabica – Delicate cup, many different subtle flavours, used for single origin and premium coffee blends – lovely drunken black.