8 a 14 años

Travel back in time and into the not-so-distant future to dissect, explore, and discover how all kinds of things do what they do! Along the way, you'll learn why cotton candy is so fluffy, how scientists built a space suit for Mars, and what goes into animating your favorite cartoons.

Look inside, take it apart, turn it over, and figure out how things work! Quippy descriptions, full-color diagrams, and brilliant photographs make even the most intimidating subjects completely accessible--and totally fun! (We're looking at you, space robots.) For every explanation, we touch on basic principles and then dive deeper. Just want to know what terraforming is? We've got you covered. Want to know how to terraform, say, Mars? We'll explain that, too.

But this book isn't just for explaining things. We'll also introduce you to the dreamers, scientists, and innovators who create this amazing stuff. You'll meet a NASA engineer, an underwater archaeologist, and a chocolate scientist. You'll learn what it's like to fly a plane into the eye of a hurricane--on purpose.

Following on the success of National Geographic's How Things Work and How Things Work: Inside Out, How Things Work: Then and Now tackles a whole new batch of extraordinary and everyday things--from man-made to natural, historic to futuristic.

Describes the physical characteristics, habits, and natural environment of the huge plant-eating apatosaurus and discusses theories on why it became extinct.

"A Plant-eating Giant:

Can you picture the world as it was many millions of years ago?

Things looked very different then.  The Earth was continually changing.

Separate continents were still forming.  There were no humans yet.  This was the Mesozoic era, a time also known as the Age of the Dinosaurs.

What are dinosaurs?"