On the 50th anniversary of its first flight, a history of the DC-3 illustrates its importance to aviation.

Consistently stunning documentaries transport viewers to far-flung locations ranging from the torrid African plains to the chilly splendors of icy Antarctica. The show's primary focus is on animals and ecosystems around the world. A comic book based on the show, meant to be used an as educational tool for kids, was briefly distributed to museums and schools at no cost in the mid-2000s.

This award-winning series presents compelling untold stories and covers a wide array of provocative subjects. "Explorer" aired for 25 years -- the longest-running documentary series in cable TV history -- before being relaunched in 2015 after a five-year hiatus. Each monthly episode of the new "Explorer" takes a similar deep dive inside a story from the pages of a recent National Geographic magazine issue, taking viewers not only to the most remote corners of the globe but also to the furthest reaches of the mind and deepest crevices of history -- on urgent missions of discovery.

"Naked Science" strips away the layers of a scientific investigation into one of the big mysteries of our time, revealing through expert analysis realistic scenarios that either confirm or deny long-held assumptions and misconceptions.