Hi, I'm John Green, and I am one of the hosts of Crash Course, which is a series of videos used by, like, teachers and students and also people who just want to lead more engaged and interesting lives.

At Crash Course, we make videos about chemistry, and biology, and history, and literature, and astronomy, and economics, and many other things. We do this because we are huge nerds, but also because we believe that high quality educational video should be available to everyone for free.

And for more than three years now, we've been able to do that. The only problem is that this is not a great business model. The good business model is either to make videos about cats on Roombas or else to make educational video that's extremely expensive that you sell to schools for tons of money.

But as much as I enjoy a cat on a Roomba, I prefer learning about mitosis. So we have a different model here at Crash Course: more than half of our budget is raised through crowdfunding. We also get grants and make money from advertisements, but you are by far our largest source of revenue.

You are the reason that we can afford such high quality props as this eagle, and our globe! It really spins! You gotta pay extra for spinning globes. Plus, no Soviet Union, which means that it's relatively recent!

Also we have to pay for writers, and education consultants, and animators, and editors, but most of our money goes into the eagle budget.

So anyway, in order for all of this to work and people to be able to see Crash Course videos for free, some people have to pay. Now, if you don't have the money or you don't want to pay, that's fine. The important thing is that you enjoy Crash Course. But if you can pay a few dollars a month, or a lot of dollars a month, then you can help us keep Crash Course going. Or even to help grow Crash Course!

Like, we've recently launched Crash Course Kids, which takes Crash Course to younger students. And we're doing lesson plans around Crash Course videos. And we'd like to continue growing, and teach even more stuff about the astonishing universe in which we find ourselves.

Also, if you support us, you can get some pretty cool rewards, so check out the campaign below, and as they say in my home town: Don't Forget To Be Awesome.