What's the difference between a Mastodon and a Woolly Mammoth?

Question

The two terms seem to be used interchangably. Are they the same animal?

Answer 1

Mastodons or Mastodonts (meaning "nipple-teeth") are members of the extinct genus Mammut of the order Proboscidea and form the family Mammutidae; they resembled, but were distinct from, the woolly mammoth which belongs to the family Elephantidae. Mastodons were browsers and mammoths were grazers.
http://en.wikipedia.org/wiki/Mastodon
The woolly mammoth, also called the tundra mammoth, is an extinct species of mammoth. This animal is known from bones and frozen carcasses from northern North America and northern Eurasia with the best preserved carcasses in Siberia.
http://en.wikipedia.org/wiki/Woolly_Mammoth#Adaptations

Answer 2

mastodons have teeth with breast-like extensions, while mammoths have teeth with narrow furrows.

Answer 3

A "Mast-o'-don" is a particularly revengeful gangster of Italian background and connections who will knee-cap you if you try to touch the main timber member supporting all the rigging aboard his sailing ship.

A "Woolly Mammoth" is the Great-great-great-great ancestor of Chewbacca, of Starwars fame. (On his Auntie Emily's side)