They are a close relative to hadrosaurs.
They are 30 feet long and around 9 feet tall. They weight 4-5 tons and have pointed claws on their thumbs. These claws could be used defensively when they get attacked.
Iguanodon is the largest, and most famous dinosaur of it's group, iguanodontids.
Though it usually walked on 4 legs, sometimes it would stand on 2 legs to reach up and chew on some delicious tree leaves.
Iguanodon had square-ish teeth that could easily chew through the plants, leaves, ferns, and bushes they ate.
Iguanodon was the second dinosaur to be called a dinosaur. This means people discovered it before most other dinosaurs in 1825.