Ever hear the joke about the librarian who shushes everyone? All the objectifying characterizations aside, librarians play a vital, yet misunderstood, role in society. These bestowers of knowledge, book organizers, or walking encyclopedias are the ultimate guides along the proverbial information highway.

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On TV, librarians are often represented as nerdy guys, sexy women, or totally mental lunatics. Not all TV librarians readily fit into these stereotypical molds, either, but they all exist somewhere on the spectrum of good and evil. The best TV librarians steer those around them to the data they need, while the worst cause problems wherever they go.

Best: Rupert Giles (Buffy The Vampire Slayer)

Rupert Giles (Buffy The Vampire Slayer)

Buffy Summers wouldn't be able to kick so much supernatural butt without the help of Sunnyvale High School's librarian Rupert Giles. Rupert's, played by Anthony Stewart Head, is Buffy's Watcher and guide; he's also really good with a computer.

In Buffy the Vampire Slayer, Buffy and her crew spend a lot of time in the library preparing to battle demons, vamps, and other creatures. With the mild-mannered Rupert's help, the Scooby Gang obtains the information they need to keep Sunnydale safe.

Worst: Tammy Two (Parks & Recreation)

Tammy Two (Parks & Recreation)

Nick Offerman's Ron Swanson from Parks & Recreation doesn't have the best taste in women, proven by his two demented ex-wives who both happen to share the name, Tammy. Offerman's real-life wife Megan Mullally plays Ron's second wife, Tammy Two, in the series.

Tammy, a librarian in Pawnee, is characterized as a conniving and ruthless woman who uses her influence over Ron to land special deals for the library. Whenever she reappears in Ron's life, viewers know she's up to no good.

Best: Flynn Carsen (The Librarians)

Flynn Carsen (The Librarians)

Instead of popular fiction books or DVDs, the librarians in TNT's The Librarians bear a much different burden: they must defend a wide range of enchanted relics that could destroy the world if they end up in the wrong hands. A spin-off of The Librarian films, the series sees Noah Wylie reprising his role as the intelligent and talented guardian Flynn Carsen.

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In the show, Carsen receives additional help from three newly-selected Librarians. Together, the four custodians protect their precious collection from an array of supernatural threats.

Worst: Miss DeGroot (Married... With Children)

Miss DeGroot (Married... With Children)

One of Al Bundy's many lifelong enemies in Married... With Children is the local librarian Miss DeGroot. Since his childhood, DeGroot had it out for Al after he insulted her appearance.

After Al checked out a book in his youth he never returned, DeGroot remained at the library for decades waiting to exact her revenge on Al. When they eventually cross paths again, DeGroot informs Al he owes $12,000 in late fees for the book, The Little Engine that Could.

Best: Barbara Gordon (Batman)

Barbara Gordon (Batman)

The librarian profession gets a major boost with Batgirl, aka Barbara Gordon, from the DC Batman comics. While she's been played by different actors in film and TV, Gordon was brought to life by Yvonne Craig in the 1960s live-action Batman series.

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Smart, stylish, and resourceful, Gordon manages the Gotham City Library by day and fights alongside Batman and Robin by night. She's also the daughter of Commissioner Gordon.

Worst: The Loud Librarian (All That)

The Loud Librarian (All That)

One of Lori Beth Denberg's best recurring characters from the Nickelodeon '90s sketch series All That is The Loud Librarian. Playing on the stereotype that librarians must maintain a quiet space, The Loud Librarian doesn't use her inside voice to lay down the law.

Instead, she screams, uses a blow horn, and engages in normal activities while chastizing any student in her school library who makes a peep. Talk about giving mixed messages.

Best: Belle French (Once Upon A Time)

Belle French in library

In Once Upon a Time, fairy tale characters come to life in a small fictional Maine town called Storybrooke. Emilie de Ravin plays Belle French, the heroine from the classic story "Beauty and the Beast."

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For much of the show, Belle manages the Storybrooke Free Public Library. It's no easy task, as beneath the library exists a vast cave system that houses not only the evil villain Maleficent but the fail-safe for the curse that has the power to destroy everything in Storybrooke.

Worst: Wan Shi Tong (Avatar: The Last Airbender)

Wan Shi Tong (Avatar The Last Airbender)

Wan Shi Tong, the Spirit of Knowledge who assumes the form of a great owl, oversees his vast Spirit Library in Avatar: The Last AirbenderAfter sharing his infinite knowledge and resources with humans in the physical, Wan Shi Tong was dismayed by how his information was used to wage war and banned all of humanity from his library.

Wan Shi Tong resents the Avatar's attempts to bridge the gap between the spirit and physical realms. Hardened from past experiences, he refuses to dispense his data riches if it means any of it will be used to help humanity.

Best: Brooke Rockwell (That 70s Show)

Brooke (That 70s Show)

Shannon Elizabeth plays the bright and ambitious Brooke Rockwell in That '70s Show. Brooke, the high school valedictorian, has a brief affair with Ashton Kutcher's character Michael Kelso, which results in her becoming pregnant.

Brooke doesn't believe Kelso will be a responsible father and partner, which puts a strain on their relationship; she eventually moves to Chicago, where she gives birth to their daughter Betsy and becomes a librarian. At the end of season eight, Kelso moves to Chicago so he can play a more prominent role in his daughter's life.

Worst: Lt. Bookman (Seinfeld)

Jerry being chastized by Lt. Bookman in Seinfeld

While not technically a librarian, Joe Bookman is a library cop who goes after Jerry in Seinfeld. Jerry never returned the copy of Henry Miller's Tropic of Cancer he checked out in 1971, and Lt. Bookman tracks him down in order to excoriate him.

Philip Baker Hall plays Bookman, who takes his job very seriously. He wants to make sure Jerry understands how he kept other library patrons from being able to read Miller's novel by holding onto it for so long.

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