That thar be a dinosawr.

"What is your favorite dinosaur?"

What a loaded question, right? For some of us it's really hard to really nail that answer down to one, or five or a hundred. Most kids have a favorite and so do most adults. Unlike the kids though, most adults favorite "dinosaur" is way off the mark.
When you ask someone that particular question and they are over the age of say...10...they'll usually ponder it a moment and reply with "pterodactyl" or "dimetrodon" or something equally awesome. Well, the major dorks and the kids in the room will make a face that equates to someone making an off-color, non-PC joke in a mixed crowd.
So. Awkward.
Actually, that's not true. The kid will just inform you that you're wrong. I'll make a face like I bit into a lemon and are trying to smile through it.

Don't be a part of the problem! EDUCATE YO SELF.

Yeah, that means dragons too. :(

Now, I'm not saying non-dinosaur creatures of the past aren't freaking badass. OF COURSE THEY ARE. One of my favorite creatures is the dimetrodon, who is in fact a pelycosaur (pie-lek-o-saur). He's not a dinosaur, but in fact a type of early mammal, which means he's like a cousin to us. Neat, right? So if you are a fan of this cool dude, which I hope you are, when someone asks your favorite dino, you can be a smartass and say, "Well actually my favorite isn't a dinosaur but a pelycosaur." But you have to say it with a British accent and be snooty. Otherwise you're doing it wrong.

Anyway.

So what is a dinosaur? There's a cool little video from The Dinosaur Show that explains what a dinosaur is in a very basic way. Awesome way to learn the bare bones, dino 101 of classifying dinosaurs. Basically, if it has legs directly under its body, has either scales or feathers, it's a dinosaur. Easy-peasy.

So, sorry to say, pterosaurs and the cool sea monster looking bastards, are not dinosaurs.
But they are super cool.

These hips don't lie! Haha!
I'm so sorry.

Dinosaurs are broken down into two main groups within the many, many, many different species. The two main groups are based on the type of hips that they have, which is either ornithischian ("bird hips") or saurischian ("lizard hips").
Ready for me to blow your damn mind?
If you don't know by now, or have some type of weird delusional denial that birds are related to dinosaurs, well...they are. Birds are the descendants of those awesome beasts that mastered the earth millions of years ago when we (our mousy ancestors) were hiding in tiny little burrows.
Get this.
The "bird-hipped" dinosaurs....are not the father  direct ancestors of the birds! Whaaaat? *que head popping*

That allosaur is having a great time.

If you take a look at the two groups side-by-side, it makes sense when you see the complete skeleton, and even more so when they're all fleshed out. The "bird-hipped" dinosaurs are the ceratopsians, the hardrosaurs and stegasaurs and such. The "lizard-hipped" flavor are the typically big meat eaters like t-rex and his buddies and some of the big sauropods or "long neck" dudes.






So, why the hell did they call them "bird-hipped" if they don't have a damn thing to do with bird ancestry!?
Good question. These classifications were made before it was known that dinosaurs were linked to birds, and also has a big thing to do with the structure of the hip bones themselves. The basic hip structure for each classification is based on how lizard hip bones and bird hip bones are shaped. This falls into some taxonomy/anatomy stuff that is a fun rabbit hole to climb down, but definitely cartwheels past the basic stuff.

So now you know some basic dinosaur 101!

Pretty rad, right?

TL;DR: you got two main categories of dinosaurs, now that you know what classifies as a dinosaur, and a whole bunch of species within those hip classifications.

So...what's your favorite dinosaur?