Although the majority of Friends' storylines focus on the main group of Ross, Monica, Chandler, Joey, Phoebe and Rachel, there are still plenty of characters in the show that are given chances to shine with their entertaining and memorable performances and narratives.

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The show was never afraid to adopt fan-favorite side characters into the main cast, or at least give them bigger roles in the lives of the central friends. Plenty of these side characters evolved into love interests for the main characters, or even recurring cameos that surprised from time to time.

Marshall Townend

Marshall Townend and Joey Tribbiani Celebrating in Friends

Although his role in the series is extremely small compared to some of the other entries on this list, Marshall Townend has plenty of memorable lines and iconic deliveries that stand among some of the show's funniest moments. He's the director of the play starring Joey and his then-girlfriend Kate.

Redditor crow_man argues that Marshall is the "most underrated side character" in the show, since nobody really talks about him when discussing the show's best characters - but the episodes in which he appears are some of the funniest and most entertaining of them all.

Leonard Green

Friends Dr Green shouts at Ross Geller

Redditor impishmisconception argues that Rachel's father, Dr Leonard Green, is one of the show's best side characters. There's certainly an argument to be made that the conflict between Rachel's parents in 'The One With The Two Parties" is some of the funniest material of the show's second season, and a lot of this comes down to the stress that this causes for both Ross and Rachel.

Rachel's parents don't appear as frequently as the Gellers', but they're a hugely important addition to the show's older character list thanks to their hilarious chemistry (or lack thereof). They're always fun to watch, and they add another layer of entertainment to some of the show's less comedic episodes.

Mr. and Mrs. Waltham

Friends Stephen Waltham overcharges the Gellers

Emily is far from a fan-favorite character, but one Reddit user argues that her parents are some of the most underrated side characters in the show. They only appear in a couple of episodes, but they're given plenty of hilarious lines and situations that make them extremely memorable.

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Jennifer Saunders' performance as Andrea Waltham is one that somehow manages to keep the mood light and refreshing throughout an extremely stressful and daring couple of episodes, in which Ross and Emily's marriage threatens to break down. She allows for a much-needed comedic interlude.

Eddie Menuek

Eddie Menuek holding his hands up in Friends

Eddie first appears in "The One Where Eddie Moves In," and it's instantly clear that the character is going to cause some hilarious trouble for Chandler now that Joey has moved out. Their relationship is one of the funniest to observe between a main cast member and a guest star, with many fans wishing the character had returned in the future.

Redditor klkruczek argues that Eddie deserves a place within the ranks of the show's best side characters, suggesting that some of his episodes are "the funniest of the series". His presence also helped develop the relationship between Chandler and Joey, which is one of the show's strongest aspects.

Jack Geller

Jack Geller visits Monica at her apartment in Friends.

Reddit user agent-65 argues that "Jack always has the best lines in any episodes he's in", which makes him one of the show's most underappreciated and underrated side characters. There's no doubt that Jack is a valuable addition to the show, particularly through his entertaining relationships with Monica and Ross.

Plenty of the show's funniest and most iconic episodes center around the endlessly quotable Jack and Judy, and the hijinx that arise from their mistreatment of their children. For example, the episode in which Jack accidentally allows Monica's childhood possessions to flood in the garage - 'The One Where Rosita Dies' - is believed by many to be one of the defining episodes in understanding the Gellers' complex relationships.

Estelle Leonard

Despite only being a side character in Friends, Estelle's "main character energy" is what sets her apart from the competition when it comes to being a fan-favorite. Redditor gondolingirl argues that she's the show's best side character, with many others going on to comment some of the character's most iconic lines.

Estelle played a huge role in Joey's rise to success as an actor, so she's much more than just the comic relief that many would characterize her as. She's just as important in Joey's life as many of his friends, so it's always touching to see their relationship - particularly in 'The One Where Estelle Dies'.

David the Scientist Guy

David and Phoebe in Monica's kitchen in Friends

Although David's full name is never revealed on the show, his alias as 'the scientist guy' seems very fitting considering the influence that his scientific work has over his relationship with Phoebe. Before the arrival of Paul Rudd's Mike, plenty of fans believed that David was going to be the one to finally settle down with Phoebe at the end of the show.

The conflict between Mike and David in the show's later seasons is both extremely entertaining and incredibly touching, as it does a lot to solidify Mike as Phoebe's true partner. Whilst Azaria has a lot of chemistry with Kudrow on screen, the character's final episodes prove that the characters aren't as compatible as they once thought. Thebenevolenttitan argues that David is one of the show's most underappreciated characters.

Gunther

Gunther and Rachel on Friends

In the wake of James Michael Tyler's unfortunate passing last year, many fans took to Reddit to share their favorite moments involving the barista. Reddit user amirtheperson confesses that Gunter was their "favorite side character," with many fans commenting that he was given some of the most quotable and memorable lines on the show.

Gunther was one of the few constants outside the main 6 friends that stuck with the show throughout its entirety, appearing time and time again to provide a few guaranteed laughs and smiles whenever he popped up on screen. Gunther spawned plenty of internet memes over the years, and it's impossible to imagine the show without him.

Janice Hosenstein

friends chandler janice

Although Chandler might feel differently, many fans on Reddit argue that Janice's many appearances throughout the show are some of the funniest and most entertaining moments of them all. Commenter redsage218 argues that Janice is the "clear winner" when discussing the show's best side characters.

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Janice is one of the only characters to appear in every season of Friends (or, at least her voice does), so it's no surprise that fans have grown so attached to her over the years. She's an extremely influential character in Chandler's personal growth, and also has plenty of unforgettable sideplots with the other friends.

Mike Hannigan

Mike and David argue after Mike walks in on Phoebe cheating on him by kissing David in Friends

By the end of the show, Mike is really more of a recurring character than a guest - but it wasn't always this way. The character wasn't even intended to become such a regular on the show, but the on-screen chemistry between Rudd and Kudrow was more than enough to prove that Mike and Phoebe are soulmates.

Redditor bloodyespresso claims that "Mike's lines still crack me up," which just goes to show how beloved the character is within the community. He's one of the only love interests in the show to have such strong friendships with the others in the group, which sets him apart as one of the most entertaining and fun to watch.

NEXT: 10 Hilarious Chandler Quotes That Prove He Is The Funniest Friends Character