What's all this doomsaying about libraries becoming obsolete? We know that libraries will thrive in the future because they're present in 23rd Century. In fact, Star Trek shows at least 3 librarians at work in the distant future.
In the original series episode "All Our Yesterdays," Kirk, Spock, and McCoy beam down to a seemingly vacant planet orbiting a star about to go nova. They discover that they are in a library. Despite the desperate circumstances, the librarian, who introduces himself as Mr. Atoz, is ready to help them.
Lifelong character actor Ian Wolfe, who plays Mr. Atoz, does a remarkably good job of carrying out a reference interview under conditions of extreme stress. He is friendly, welcoming, an advocate for the utility of libraries, and maintains the confidentiality of his patrons.
Lt. Mira Romaine is a bit less impressive in "The Lights of Zetar," but that may be excused because that episode showed her on her "first deep space assignment." All librarians are a bit shaky when fresh out of library school. And we don't see much of her at work at Memory Alpha, the location of her first assignment.
Scotty has a crush on Lt. Romaine, who evidently reciprocates his sentiments. Although she struggles with her new working environment, Romaine rises to the challenge by the end of the episode, ending the Zetar threat to the security of her library.
The Enterprise D was wrecked at the end of Star Trek Generations. A later movie, Star Trek: Insurrection shows the cast of The Next Generation on board a new vessel: the Enterpise E. This is a new Sovereign-class vessel that evidently boasts a library.
A deleted scene from Insurrection shows Commander Riker and Counselor Troi working inside a library. There are study carrels, computer access stations, and a bespectacled librarian behind a service desk. We never learn the librarian's name, but she's uniformed as a sciences division lieutenant portrayed by actress Lee Arnone-Briggs. Riker and Troi misbehave by making noise, throwing paper balls, and getting way too frisky with each other. Even though both officers outrank her, the librarian does not tolerate such behavior in her library. She shushes them.
Lee Arnone-Briggs's librarian does not shush them the way that I typically shush noisy patrons at my library. But librarians must carry an array of shushes to use in different situations with different people.
Bonus Librarian: Captain James T. Kirk. In the animated series episode "Bem," Kirk comments to Spock that he might have considered a career in librarianship. This idea could inspire some great fan fiction.