I love Iguanas!  They have always been my favorite reptile.  First described in 1768 by an Austrian NIcolaus Laurenti.
What sets Iguanas apart from other reptiles like Lizard?
Well for one they can range in length, including their tails.  The name was derived from the Taino name "Iwana".
That's really interesting, I always thought it was a unique name. 
There are actually two types of Iguana as well.  The Green Iguana and the the lesser Antilles Iguana.
So, what's the difference?
The lesser Iguana is a little bit smaller.  Both possess a dewlap though, which is a row of spines running down their backs to their tails.
Awesome. It sounds like a little dinosaur.
Dinosaur
Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic period, between 243 and 233.23 million years ago, although the exact origin and timing of the evolution of dinosaurs is the subject of active research. They became the dominant terrestrial vertebrates after the Triassic–Jurassic extinction event 201 million years ago; their dominance continued through the Jurassic and Cretaceous periods. The fossil record demonstrates that birds are modern feathered dinosaurs, having evolved from earlier theropods during the late Jurassic Period. As such
and endangered due to habitat destruction, introduced feral predators, hunting, and hybridization with introduced green iguanas.
The word "iguana" is derived from the original Taino name for the species, "iwana".
In addition to the two species in the genus "Iguana", several other related genera in the same family have common names of the species including the word "iguana".
Anatomy and physiology.
Iguanas can range from in length, including their tail. The two species of lizard within the