On September 22, Friends turned 25 years old. The show has endeared itself equally to Gen X and Millennials, as well as to people in other countries, who may not speak English. “The Friends Effect,” as it’s known, refers to non-native speakers learning American English from watching the sitcom. Variety recently reported on how over the years, foreigners have learned English through the show's subtitles.

“I was so in love with their accents,” Matt Ainiwaer, a native of China’s Xinjiang region, told Variety about the show. “I love American accents a lot. So I just tried to copy them—like, imitate them. I decided to tape-record it myself and get as close as possible to their accents.”

RM, the leader of Korean boy band BTS, told Ellen DeGeneres he learned English because his mother forced him to watch episodes of Friends. “All the Korean parents make their kids watch Friends,” he said. “I thought I was kind of like a victim at that time … Firstly I watched with Korean subtitles, and then next time I watched with English subtitles.”

In 2017, The New York Times reported on how several Latino Major League baseball players—from the Dominican Republic, Venezuela, the U.S., and Mexico—learned English or improved their English from watching Friends every night.

“It’s funny, because it’s such colloquial English,” Friends co-creator David Crane told Variety. “We actually wrote in the script all the times they say ‘like’—that’s on us. Those are in the scripts, all the uhs and the likes. We actually scripted all of that, so the idea that someone’s learning English with all of our weird inverted sentences—we certainly didn’t write it as a grammar primer.” But Friends co-creator Marta Kauffman told Variety, “The fact that it has taught people English is just amazing icing on the cake.”

Friends is far from the only television show people use to learn English, however. In 2012, a Kaplan International survey found 82 percent of respondents said TV helped them learn English. Although 26 percent—the highest percentage—said it was Friends that helped the most, that was followed by The Simpsons with 7 percent.

Melissa Baese-Berk, associate professor of linguistics and director of the Second Language Acquisition and Teaching program at the University of Oregon, told CNN three tips for learning a language from a TV show: The program should be engaging, it should have subtitles, and it should have repetitive storylines, like Friends. And learning a new language works for both English and non-English speakers alike—watching telenovelas, for example, is a great way for people to learn Spanish.

[h/t Variety]