This is an Eastern American Toad, anaxyrus americanus americanus. He's a big fella, about the size of a baseball. They have a pretty unique call, described as a shrill 6 second whistle. This is what is known as a true toad.
They say that all toads are frogs, but not all frogs are toads, but I don't understand this line of logic. Frogs and toads together are amphibians from the order Anura. Within this order are two superfamilies, Bufonoidea (true toads), and Ranoidea (true frogs). Since all the species in the order Anura are considered frogs, then I guess toads are also frogs, but this seems to be based more on informal naming than actual taxonomy.
Anyway, this dude knew how to pose.