Concrete Contraction or Control Joints vs. Expansion joints

What is the difference between control/contraction joints and expansion joints?

Here is a great article about control contraction joints:

http://www.cement.org/for-concrete-books-learning/...

Here is a good link for spacing distances of control joints

 http://www.cement.org/images/default-source/contec...

An expansion joint is a joint that gets cut through the entire depth of the concrete, or is done with Jolly Board being placed before concrete is poured.  Jolly Board Expansion Joint Filler is manufactured from water resistant, bitumen impregnated, cane fibre.  Here is a link:

http://www.jollyboard.com/Products_Projects.aspx?S...

Here is a great link for concrete knowledge:

http://www.cement.org/for-concrete-books-learning/...