I am surprised no one has mentioned this wonderful graphic (Credit: [Espresso Field Guide][2] by the aptly named [Jay Mug][3] ):

![enter image description here][1]


  [1]: http://i.stack.imgur.com/218q7.jpg
  [2]: http://www.jaymug.com/post/11408322926/espresso-field-guide
  [3]: http://www.jaymug.com/