A lot of things can contribute to a television character's popularity. Some are loved for being central to the show and at the heart of some of its iconic storylines. Some are loved for being fantastic comic relief, adding levity and wit to any scene they're in. Some are loved for being good friends or the sort of person who people wish they knew in real life.

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Some, on the other hand, are popular just for being cool. Whether it is their aesthetic, their deeds, or their personality, there is something about them that just innately draws people in. This gives them a certain factor that is hard to authentically generate, a level of cool.

10 Mike Ehrmentraut Is A Killer With A Soft Side (Breaking Bad)

Mike Ehrmentraut from Breaking Bad

Despite its fairly realistic look into the downsides and brutality of American drug dealing, Breaking Bad manages to produce no small number of characters whom viewers enjoy every second they're on-screen. A standout is Mike Ehrmentraut, a character who is first introduced as a minor employee of Saul Goodman's and becomes a major player.

Fans love Mike for his no-nonsense demeanor, his quiet contempt for most of the other players in the drugs industry, and for his vaguely paternal relationship with Jesse Pinkman. He stands out as a cool character for his deeply caring relationship with his granddaughter and for being one of the most lethal characters in Breaking Bad.

9 Yelena Belova Is In A League Of Her Own (Hawkeye)

Florence Pugh as Yelena Belova in Hawkeye series

First appearing in the films before making a major appearance in Hawkeye, Yelena Belova has proven to be one of the most popular characters of Phase 4 of the Marvel Cinematic Universe. Her very concept is a cool one at its core, being a lethal spy trained from a young age who has since rebelled and regained her agency.

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In Hawkeye, however, Yelena elevates herself. She steals every scene she's in with a mixture of humor and impressive moments. She can outfight and outtalk any other character in Hawkeye, and only holds back because of her vendetta against Clint Barton and genuinely good rapport with Kate Bishop. As such, fans look forward to her next performance.

8 Shepherd Book Is A Preacher With A Dark Past (Firefly)

Shepherd Derrial Book from Firefly

All of Serenity's crew in Firefly are cool in one way or another. From snarky and bold captains to barely-contained amoral mercenaries, every member of the crew stands out and has something about them that fans can describe as simply awesome.

A character with less focus who captivates fans, however, is Shepherd Book. Proclaiming to be a simple preacher, Book is already cool by managing to be a moral center of a group of rough and gritty mercenaries and criminals. He even gains their respect. However, he can also handle a gun and has a dark past involving the Alliance, drawing fans to him more.

7 Lagertha Is A Shield-Maiden And Jarl (Vikings)

Lagertha in combat in Vikings

In terms of historical groups, few capture the public imagination in terms of cool like the Vikings. Despite acting as raiders and warriors across three continents, their religion, culture, and combat prowess have cemented them in the imagination of audiences across the world. As such, many of the cast of Vikings say and do cool things almost constantly.

In terms of coolness, Lagertha stands out to fans. Initially Ragnar Lodbrok's wife, she becomes a more important character in Vikings until she is a major character in her own right. As an outspoken and impressive Shield-Maiden, she appeals to fans for defying gender conventions and being one of the most able combatants in the cast.

6 If Daryl Dixon Dies, Fans Will Riot (The Walking Dead)

the walking dead season 11 daryl

Despite Rick Grimes being the unquestioned protagonist of The Walking Dead since its first episode, some characters have captivated the audience from their first appearance. Daryl Dixon is the most major of these, having spent significant lengths of time as an audience favorite.

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Although he is beloved for his extensive development, relationship with others, and soft side, it is because his coolness captured fan attention that he's had the chance to demonstrate them. Whether it's because he's a solitary hunter with a crossbow or prone to violence but more moral than his brother, something about Daryl screamed to fans of early seasons. Daryl is The Walking Dead's most solidly popular survivor.

5 Gene Hunt's Coolness Exists Alongside His Downsides (Life On Mars)

Detective Chief Inspector Gene Hunt lounging atop his car in Life on Mars

The major theme of Life On Mars is the comparison between the modern policing techniques, the sensibilities of protagonist Sam Tyler, and the culture of 1970s police. This is embodied by Detective Chief Inspector Gene Hunt. As Hunt openly admits, he is short-tempered, intolerant, not a fan of procedure, and quite unacceptable to a modern-day audience.

However, even the writers of Life On Mars and Ashes To Ashes were shocked by how popular Hunt became to audiences. While always intended to be liked, the character became seen as something of a sex symbol, even as the show and other characters made sure to condemn many of his actions.

4 Rupert Giles Becomes Far Cooler (Buffy The Vampire Slayer)

A character portrait of Rupert Giles from Buffy the Vampire Slayer

When he is first introduced, Rupert Giles from Buffy The Vampire Slayer initially appears to be the opposite of cool. He is a stuffy English librarian who spends much of his time being hit on the head and losing when sparring with Buffy. As his character is explored, however, he becomes one of the most impressive of the cast.

The turning point likely comes in season 2 when Giles launches a one-man assault on Angelus that succeeds in putting the vampire on the back foot for the first time all season. From there, he goes from strength to strength. He becomes one of the cast's best fighters, reveals himself as a capable sorcerer, and becomes one of the more morally ambiguous figures in Buffy.

3 Arya Stark Keeps Developing Skills (Game Of Thrones)

Arya Stark fights the dead during the Battle of Winterfell in Game of Thrones.

One fairly simple way to make a character cooler is to give them interesting abilities. Although, this has to be carefully measured so as not to make them overpowered or a 'Mary Sue'. In Game Of Thrones, Arya Stark has always been one of the more popular Stark siblings but in the eyes of many fans, she simply gets cooler as her story goes on.

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From simply an enthusiastic and expectations-defying young girl, Arya becomes a capable liar, an exceptional sword fighter, a skilled magical assassin, and one of the most lethal members of the cast. She remains popular through to the end of Game Of Thrones and is a firm fan favorite.

2 John Constantine Is A Never-Ending Barrage Of Wit And Talent (Constantine)

Matt Ryan as John Constantine leaning against a pillar in Constantine show

Few characters are cool enough to survive the cancellation of their show. Constantine had some moderate popularity, but not enough to keep it on the air. Appreciation for the title character and Matt Ryan's portrayal, however, was high enough to get the character to first appear on Arrow and then make the move to Legends Of Tomorrow as a main character.

Much like in his comic book incarnation, John Constantine is beloved by fans for being transgressive, a force to be reckoned with, witty, and down-to-earth. He's grittier than many of the characters in Legends Of Tomorrow, but not to the point of silliness, and constantly brings levity with quips and his bad luck.

1 Rosa Diaz Is The Standout Cop Of The Nine-Nine (Brooklyn Nine-Nine)

Rosa Diaz in a team briefing Brooklyn Nine Nine

From the very start of Brooklyn Nine-Nine, Detective Rosa Diaz is singled out as one of the coolest characters in the show. She is the most dangerous and short-tempered member of the squad, though never lets it interfere with her duties as an officer, and is highlighted as one of the most ethical officers in the squad.

She accompanies this with an incredible number of impressive skills and a mysterious past that is only partially revealed as Brooklyn Nine-Nine goes on. An entire episode even has a plotline about her coolness rubbing off on Charles Boyle. For her unique personality and strong moral center, fans are deeply appreciative of Rosa Diaz.

NEXT: 9 Movie Characters Who Don't Deserve Their Popularity