Jim Henson and his creative team constructed several optical illusions to make the Muppets appear as though they walked through the real world.

Watch Jim Henson explain how to make a Muppet.

Before 'The Muppet Show,' Jim Henson produced slapstick coffee commercials featuring the puppets.

Jim Henson's 1986 film 'Labyrinth' was initially a commercial failure in the US, though it slowly gained an audience that now considers it a cult classic.

Jim Henson and his Muppets were part of the first season of 'Saturday Night Live' because NBC was hoping to tamp down Lorne Michaels' countercultural plans for the show.

Fascinated by the 1960s counterculture, Jim Henson tried to build a psychedelic nightclub.

For 'Labyrinth,' the Jim Henson Company erected a 15-foot-tall character named Humongous, the largest puppet the company had ever built.

'The Muppet Show' debuted in the UK because it was rejected by every US network.

Jim Henson's lone Oscar nomination was for an experimental short film he made in the '60s that features no puppets.

Watch episodes of 'Sam and Friends,' the earliest show featuring the Muppets.

Jim Henson's 'Fraggle Rock' was the first American TV series to air in the USSR.

'Follow your enthusiasm. It's something I've always believed in. Find those parts of your life you enjoy the most. Do what you enjoy doing.'

- "Muppets" creator Jim Henson (1936-1990)

Cookie Monster evolved from the Wheel Stealer, a monster obsessed with a wheel-shaped cheese snack.

Check out one critic's guide to the best Muppet movies, including 'The Great Muppet Caper,' 'The Muppets Take Manhattan,' and more.

'(Kids) don't remember what you try to teach them. They remember what you are.'

- "Muppets" creator Jim Henson (1936-1990)

Wally Feresten is the man behind the show's iconic cue cards

"SNL" obsessives are familiar with the show's cue cards, which occasionally appear on air in fourth-wall-breaking segments. They might even recognize Wally Feresten, the man who's been handwriting (and holding) them since 1990. This podcast interview delves into Feresten's curious life behind the scenes at "SNL" and his unexpected turns in front of the camera.

Judy Garland's body double wore a sepia dress in the most famous scene from 'The Wizard of Oz' to create the illusion of moving from a black-and-white world to a color one.

A famous scene from "The Wizard of Oz" features Dorothy leaving behind her home in Kansas and walking into Oz. The filmmakers wanted the character to exit a colorless world and enter a Technicolor one, though the nascent technology required more than some clever postproduction tricks. The scene was painted sepia, as was Judy Garland's body double's dress. As she walks through the door, into Oz, the camera turns away. Then, Judy Garland strides back into frame, wearing her iconic blue dress.

The art of miniature sets in Hollywood

Many films utilize meticulously designed miniature sets to produce scenes that would otherwise be too big to film. While artsy filmmaker Wes Anderson is well-known for reviving this technique in an idiosyncratic style, more mainstream films like "Star Wars" and "Inception" rely heavily on small-scale sets filmed in such a way as to make them appear normal-sized. This nine-minute video breaks down how it all works.

2 'Simpsons' producers break down the show's turning points

Longtime director David Silverman and showrunner Matt Selman walk you through some of the show's biggest turning points, from the early days on "The Tracey Ullman Show" through its biggest guest stars and eerily accurate predictions.

'Potter Puppet Pals' was one of the internet’s first viral videos

Created by animator Neil Cicierega in the early 2000s, Potter Puppet Pals featured felt puppets parodying the Harry Potter characters. Its 2007 video “The Mysterious Ticking Noise” became an early YouTube sensation, amassing more than 200 million views.

Most Mardi Gras floats are constructed from foam and papier-mache

The moving sets were originally drawn by mules and made of wood. Now, they're motorized and intricately crafted from foam and papier-mache. This virtual tour of Mardi Gras World—a New Orleans warehouse responsible for floats for various krewes, as well as for Disney and Six Flags—showcases their vibrant designs.

The science of optical illusions

The human brain has developed cognitive shortcuts to help us navigate in a world where our visual senses are constantly bombarded of information. But these shortcuts can also be exploited, tricking the brain into telling us something is happening when it really isn't. This short video unpacks the neuroscience behind some of the most common (but perplexing) optical illusions.

The first horror movie is believed to be George Méliès' 1896 short 'The Haunted Castle,' which pioneered special effects.

Dolly Parton hosted two separate variety television shows called 'Dolly.'

The best celebrity cameos on 'The Simpsons'

As the show became a pop culture sensation in the late '80s, it began attracting celebrities eager to get in on the fun. This list ranks some of the best of those appearances, including Meryl Streep, Paul McCartney, and Dustin Hoffman.

Watch Walt Disney's early innovative film, 'Alice's Wonderland,' which innovated the use of animated characters in the real world.

Over the years, Baum’s story has had several adaptations and reinterpretations

The original 1900 book, ‘The Wonderful Wizard of Oz,’ has been adapted in various forms for various audiences. There’s been a Muppet-centric Oz, a 3D-generated Dorothy, and one that imagines an adult Dorothy living as a children’s author in New York, just to name a few.

'Steamboat Willie' was inspired by 'The Jazz Singer'

Walt Disney was mesmerized by Al Jolson's "The Jazz Singer" and the way it used synchronized sound, which synced film with audio. He replicated that effect in “Steamboat Willie," producing the first animated film to do so.

Before becoming a famous weatherman for the Today show, Willard Scott created 'Ronald McDonald' for a Washington DC location in 1963.

Watch a medley of Pets.com commercials with the famous sock puppet mascot

Pets.com used a sock puppet decorated like a dog (operated by comedian Michael Ian Black) as the company's mascot. The sock puppet became synonymous with the brand. An auto lender company called BarNone Inc. later purchased the sock puppet for $125K and rebranded it with the slogan "Everybody deserves a second chance."

The sophisticated math jokes of 'The Simpsons'

"The Simpsons" has always been a slyly sophisticated show and has featured more than a few references to complex mathematical concepts. That's largely due to its writers' room, which has featured more than one writer who studied math before transitioning to comedy.

Go behind the scenes at the Macy’s Parade Studio

With dozens of balloons and floats, and thousands of costumes, the Macy’s Thanksgiving Day Parade requires year-round planning to pull off. Go behind the scenes with the designers and builders who make the magic happen. See how the floats come together and what makes this annual spectacle a reality.

Watch the 'Star Wars Holiday Special,' a 1978 spin-off that became a cult classic

The CBS television special is a hokey variety show that was widely panned after it aired and, as a result, was never officially released on home video. George Lucas had little involvement, though it did feature the original cast alongside guest stars like Bea Arthur. Interestingly, it also features Boba Fett's first appearance.

Meet Clever Hans, the 1900s horse that was believed to be able to solve math equations and read German

When Clever Hans was prompted with math questions, he responded by tapping his hoof to indicate his answers. Even a panel of experts found no indication of trickery in the horse's demonstrations. However, psychology student Oskar Pfungst found that Hans stopped tapping once a subtle cue on his owner's face told him to stop. The cues were so subtle that Wilhelm von Osten didn't even know he was giving them.

'Special effects' have evolved alongside Hollywood

Since the early days of moviemaking, directors have played with perspective to create incredible effects on the screen. From Buster Keaton to contemporary CGI, this 30-minute documentary details the amazing evolution of Hollywood's special effects.

The 1939 film adaptation of 'The Wizard of Oz' reimagined L. Frank Baum's book 'The Wonderful Wizard of Oz' for a new age, using technological breakthroughs to depict Baum's fantastical text.

The creator of 'The Simpsons' made his characters yellow so they would contrast with everything else on TV.

The horror film 'Obsession' borrowed its premise from a 'Simpsons' episode, which was itself based on a classic British ghost story.

Francis Ford Coppola once directed an episode of 'SNL' featuring experimental composer Philip Glass as musical guest.

The story behind Conan O'Brien's most celebrated 'Simpsons' episode

"Marge vs. the Monorail," an episode from the show's fourth season, is widely considered not only one of the best 'Simpsons' episodes, but one of the best sitcom episodes in general. In this detailed history of it for The Ringer, writer Conan O'Brien, then a 28-year-old fresh off leaving "Saturday Night Live," explains how "The Music Man," disaster movies, and a strange billboard inspired the script.

'Steamboat Willie' was the first film to feature Mickey Mouse

This short film introduced Mickey Mouse, the character who would define the Disney brand, to the world. It might be almost 100 years old, but you'll be surprised at how much humor still holds up.

A 'Simpsons' writer on the show's inadvertent predictions

Some have noted that "The Simpsons" has accurately anticipated a number of events years before they happened. In this interview, showrunner Al Jean explains how these unintentional predictions came about and why he believes the events were not so much visions of the future as educated guesses.

Pixar's first animated film was 1986's short 'Luxo Jr.,' featuring characters still used by the studio today.

Pixar's earliest days began with a handful of academics developing the technologies they thought might make fully animated movies possible.

One man provides temporary vocals for nearly every character on 'The Simpsons'

Early in the production process, voice actor Chris Edgerly voices hundreds of characters so animators can create preliminary sketches. In this interview, he explains how he learned to mimic the characters' unique voice and tics.

Dickens' live readings sometimes used visual projectors that predated cinema

Dickens was interested in adapting his work in various forms. With his live readings, he sometimes used a 'magical lantern,' a popular tool that projected moving slides. In addition, some stage plays of Dickens' work that included ghost scenes used the magical lantern to cast apparitions on stage.

Watch Billy Joel deepfake himself in the 'Turn the Lights Back On' music video

Though deepfakes are often synonymous with manipulation and bad intentions, some artists have found creative uses for the technology. In this example, Billy Joel depicts himself in various eras of his career in keeping with the song's nostalgic message.

Pixar's RenderMan software, which turned code into graphics, changed the way Hollywood produced special effects.

The original ending to 'Rudolph the Red-Nosed Reindeer' was changed after viewers voiced their disappointment

The movie's TV premiere on December, 6, 1964, ended with Santa choosing Rudolph to help him deliver presents across the world. However, young viewers were disappointed that Rudolph never fulfilled his promise to rescue his friends from the Island of Misfit Toys, which he'd promised to do earlier in the film. The producers reworked the ending, correcting the plothole, before the movie was broadcast again in 1965.

See historic Macy’s Thanksgiving Day Parade photos

Snoopy and Bullwinkle and Clifford, oh my! This slideshow has photographs of all those characters (and more) from when they debuted as balloons at the Macy’s Thanksgiving Day Parade. These photos span from the original parades in the 1920s through the early 2000s.

The jump scare, a horror genre trope, was invented to keep costs low

RKO Pictures hired Val Lewton to produce horror films in the Universal model: small budgets, big spectacles. His first movie was 1942's "Cat People" and he used tension and offscreen terror to save money. A perfect example is the movie's jump scare, a misdirection technique that catches viewers off guard.