Not given credit for his contributions to molecular chemistry for half a century, Amedeo Avogadro was eventually recognized for his work and now holds the honor of having his name attached to the ubiquitous chemical quantity that all high school chemistry students know well; the mole (Avogadro's number). In this podcast, Avogadro's ideas are discussed and the classification of matter from a particulate perspective is described.  Listeners will come to see why Avogadro's work was so important and why he deserves his name on the unit used most commonly in chemical calculations.