title_body: Are robusta and arabica the only bean varieties?
upvoted_answer: Coffea Arabica and Coffea Canephora are the only two species of plants whose beans we use to make coffee - Arabica and Robusta respectively. 
  
  However, you may have heard of other 'types' of coffee that might be confusing. For example Peaberry Coffee is not actually a separate bean type. 5-10% of harvested coffee berries contain only one bean (instead of two). These are usually discarded, but sometimes are collected and sold separately. They are normally Arabica beans.
  
  Furthermore, since 2008, 9 new species of coffee plant have been discovered. These are not currently cultivated for beans though, as far as I can tell (though some species contain traits which would be desirable1 - self-pollination and caffeine-free beans).
  
  
  
  1. Desirable for some people...