Millions of years ago, massive reptiles roamed the Earth. Dinosaurs came in all shapes and sizes, and left behind fossilized remains when they became extinct. Scientists study these fossils to learn more about these special creatures – and we’re still learning new things about them to this day.

Dinosaur names are long and complex, but the name itself helps identify some key information about that particular species. Here are some common dinosaur names and pictures to help you identify them correctly.

Tyrannosaurus rex

Tyrannosaurus rex (or T. rex for short) means “tyrant lizard king” – and these massive lizards certainly struck fear into anything unfortunate enough to cross paths with them. Standing about 13 feet tall at its highest point and reaching over 40 feet long, the T. rex is one of the largest carnivorous dinosaurs to roam the Earth. Various studies suggest it weighed in at a whopping 19,000 pounds (or more!) and could chase prey at a speedy 10 to 25 mph. (source)

Stegosaurus

These “roofed lizards” were named for large plates that early scientists believed covered their backs like shingles. Evidence suggests that these plates actually rise up straight from its back and extend from the tail to the neck in two impressive rows. They have spiked “thagomizers” (so named from a 1982 cartoon) that were likely used as a defense mechanism from predators. Considering that the Stegosaurus possessed a brain the size of a hotdog – a built-in weapon definitely came in handy. (source)

Triceratops

First discovered in the American West in 1887, the Triceratops is a large “three-horned face” dinosaur that roamed the earth around 65 million years ago. They were about the size of an elephant, standing 30 feet tall and weighing almost 16,000 pounds. The two prominent horns on top of its head could grow to 3 feet in length, while the horn on its snout may have been made of mostly keratin (like that of a rhinoceros).

Archaeopteryx

These massive “ancient feather wings” lived in the late Jurassic Period nearly 150 million years ago. While they weren’t large – about the size of a raven – they are one of the only true “flying dinosaurs”. Other winged reptiles like Pteranodons and Pterodactyls are part of a different scientific classification than true dinosaurs. Archaeopteryx had asymmetrical flight feathers, a long bony tail, and sharp claws and teeth. (source)

Brachiosaurus

The uniquely warm-blooded Brachiosaurus (or “arm-lizard”) lived in the late Jurassic Period with the likes of the Triceratops and T. rex. Their front forelegs were longer than their back legs, and their exceptionally long necks gave them an awkward giraffe-like appearance. They stood about as tall as a four-story building! (source)

Velociraptor

While these terrifying “speedy thieves” terrorized the poor visitors to Jurassic Park, they were not nearly as formidable in real life. Standing about as tall as a fully grown turkey and weighing a little over 30 pounds, the Velociraptor was a pretty formidable predator – if you happened to be a frog. They likely had feathers, but had lost their ability to fly. Despite their small size, they may have hunted in packs, and were equipped with a sickle-shaped retractable claws on each foot. (source)

Spinosaurus

These “spined reptiles” were named for the sail-like fin that stood up along their backs. These large carnivorous dinosaurs lived around 93 – 100 million years ago, and were even bigger than the T. rex! They could be nearly 60 feet long and weigh almost 10 tons. (source)

Allosaurus

The Allosaurus, or “different lizard”, was so named due to its unique vertebrae. Some of these bones were concave and contained shallow cavities. This gave them an hourglass-like appearance, and they may have contained air sacs – a feature found in some modern-day birds. These sacs likely indicate that the Allosaurus had lighter bones than other dinosaurs of its size, but it was still a formidable predator. Standing around 40 feet tall and weighing 3,300 pounds – you wouldn’t want to cross paths with one either! (source)

Dilophosaurus

These “two-ridged” carnivorous theropods were fast, deadly, and possessed plenty of sharped curved teeth. It’s colloquially known as “the best worst-known dinosaur” – while we have plenty of Dilophosaurus fossils, we still don’t know a ton of things about it. They may be more closely related to birds than scientists originally thought, but they were once known as the largest land animal in North America in the Early Jurassic period. (source)

Apatosaurus

Due to a fossil mixup in the late 1800s, the Apatosaurus was incorrectly identified as a Brontosaurus. Unfortunately, the Apatosaurus was stuck with its Brontosaurus beginnings and the original name was still popular for many years. Some scientists still believe that they are two distinct species, although they both have long necks and slim tails. Apatosaurus means “deceptive lizard”, as its bones resemble those of large aquatic reptiles called mosasaurs. (source)