Charcoal is surprisingly interesting stuff. It's made by exposing wood to high temperatures. The resulting material can later be burned to create a very high-temperature fire, useful for metallurgy, glassmaking, and—let's face it—barbecuing.
Traditionally, charcoal creation was an occupation, and that job has been around for thousands of years. Historically, charcoal was made by burning columns of wood in a way that prohibited some of the wood from combusting, but exposing it to heat and eventually turning it into charcoal. And, of course, this still works, though there are more efficient (and environmentally sound) ways to do it.
This brings us to Primitive Technology, a YouTube channel that I find both mesmerizing and educational. In today's installment of Primitive Technology, we see how to make charcoal using materials you'd find in a typical forest. It takes days, but the resulting charcoal is pretty impressive. Enjoy:
For more details behind the project, there's a lovely writeup on the Primitive Technology blog. If you're curious what the modern process is, check out this how-it's-made video.