We’re all probably familiar with the canned Laughter that takes place on television sitcoms, but how and why did this laughter, known as a Laugh track, get started?

Added laughter in television shows can be traced back to a sound engineer named Charley Douglass, who worked at CBS in the early days of television in 1950. Douglass didn’t like how studio audiences during tapings of television shows would laugh at the wrong moments or not at the right moments, or they would either laugh for too long or too loud.

Adding laughter to a show wasn’t something entirely new, however. The technique of using recorded laughter had first been used during radio programs before the rise of television. Douglass borrowed these techniques and adapted them for television. He took laughter recordings and changed them according to what he wanted the laughter to be. He soon had a machine full of laugh tracks. These laugh tracks were debuted on The Hank McCune Show in 1950.

Douglass’s laugh tracks soon became an industry standard as the practice of adding canned laughter at specific moments of a show became more popular. The use of laugh tracks was not without controversy, however, with some producers hating them but seeing them as necessary. Many producers chose to see them as a way to improve the involvement of the viewing audience with the viewing experience, as the audience expected an audience to be present during the taping of a show.

One of the first shows that didn’t use a laugh track early on was I Love Lucy. The production used the “multi-camera filming technique” and a live studio audience. This allowed different angles of the same scene at once, thus extending the time for an audience to react to the joke using real laughter. This same technique that used an audience’s real laughter was implemented in other shows. But the run of I Love Lucy, and this technique in the 1950s, only slowed the eventual widespread use of the laugh track. It was even adopted for several animated series in the 1960s, such as The Jetsons and The Flintstones.

Even some shows without a studio audience couldn’t escape the laugh track. The CBS comedy Hogan’s Heroes was shot in 1965 with a single camera and no audience, but the network wasn’t comfortable with the format. They required two test versions of the show with and without the laugh track inserted. Test audiences had a better reaction to the laugh track version, which ensured that other shows in the future shot in the same format with or without an audience would be subjected to the canned laughs.

Other areas of the world were also struggling with whether they would use a laugh track. In the United Kingdom, all the BBC comedy shows employed a laugh track, but in 1981, when The Hitchhiker’s Guide to the Galaxy was first screened, it included a laugh track to comply with the wishes of the BBC, but producers dropped it before the first broadcast.

Countries in Latin America got around using a laugh track by employing live studio audience members to laugh at certain moments of the show called reidores or “laughers,” and shows in Mexico and Canada only used laugh tracks sparingly, mostly resisting the way it was being used in the United States.

For the next 50 years, many shows used laugh tracks to varying degrees. Sometimes they were in their proper place, eliciting an increase in laughter for a funny scene, joke, or situation, but many times they were overused by putting in laughter at almost all points in a show that wouldn’t elicit that much laughter from a live audience.

But by the beginning of the 2000s, the use of a laugh track slowly began fading out, and many popular shows stopped using it (one exception would be The Simpsons, which didn’t use a laugh track and started in 1989). Popular early 2000s shows that didn’t use a laugh track were Curb Your Enthusiasm (2000), Scrubs (2001), The Office (UK)(2001), Arrested Development (2003), The Office (US)(2005), It’s Always Sunny in Philadelphia (2005), 30 Rock (2006), and later shows such as Community (2009), Modern Family (2009), Parks and Recreation (2009), and New Girl (2011), to name a few.

The effectiveness of the laugh track is still up for debate. Did it engage an audience with a television show’s joke? Or was the laugh track, as actor David Niven said in 1955, “the single greatest affront to public intelligence I know of.” (Niven, of course, was the star of such notable movies as The Charge of the Light Brigade, A Matter of Life and Death, The Guns of Navarone, and The Pink Panther.)

Studies have been done on the effectiveness of the laugh track. A study in 1974 showed that viewers were more likely to laugh when a show had a laugh track, but a study in 2002, which compared Seinfeld, which had a laugh track, to The Simpsons, which did not, showed that volunteer viewers of each show had a near-identical pattern of brain activation. Researchers found that when viewers saw something as funny, regions of the left hemisphere of the brain showed increased activity.

It could be that the laugh track does add to the engagement with a show, or it could be that viewers don’t need help in knowing when to laugh. Only time will tell if the laugh track will become a thing of the past.

Sources: BBC, Britannica, JSTOR Daily, Science News