This illustration was created by Lokesh Dhakar and the original can be found on his blog: http://www.lokeshdhakar.com/2007/08/20/an-illustrated-coffee-guide/

Coffee is a tropical tree that produces fleshy berries which contain the actual coffee bean. Generally, coffee grows in two tree varieties, Arabica and Robusta. Arabica is more sensitive and requires more attention while Robusta is more hardy and stronger of the two. While Arabica trees yield less beans than Robusta, their berries are more flavor-able and generally more expensive. Robusta has more caffeine content and generally a stronger aroma and more acidity. Robusta being the less expensive variety is used as the main ingredient in commercially blended coffees (the supermarket variety), it is also used in stronger European espresso varieties. The largest coffee growing countries are Brazil, Columbia, Indonesia, Ethiopia and Kenya. Coffee beans are hand picked, de-fleshed and then air dried, they are only roasted within weeks of their actual consumption.

These are some rough approximations:

• A commercial large-size coffee cup uses: 20-25 grams of ground beans.
• A kilogram of green coffee beans costs approximately:  US$2
• The estimated cost of roasting a kilogram of coffee is: 40 cents 
• A kilogram of green beans once roasted and dried, is reduced to about: 750 grams
• This then produces on average: 30 large cups of brewed coffee
• In coffee price alone, a cup costs approximately: 8 cents

This however does not tell us anything about the cost of producing a cup of coffee for commercial purposes, the actual numbers vary greatly depending on so many variables. We will tackle these estimates in future posts.