Librarian

A librarian is a professional worker in a library. Although librarians are traditionally associated with collections of books, they are experts in the organization and retrieval of information in any format.

Examples:

Gramophone records and compact discs
Photographs and videotapes
Newspapers, magazines and scientific journals
Computer databases
Referrals to other community organizations and government offices.
Suggesting appropriate books for children of different reading levels, and recommending novels for recreational reading.

Librarians can be found be found in many areas. Public libraries, public schools and university libraries are the most common employers. Librarians can also be found at businesses, government departments, hospitals, law firms, museums, and other large organizations where academic research is performed or that store large quantities of information.

It is usual for a librarian to have an MLS (Master of Library Science) degree from an accredited university. Library technicians (also called assistant librarians or library assistants) may perform duties such as searching for items in the library catalog or basic cataloging, but lack the Master's degree.

The specific duties vary depending on the size and type of library and number of employees, but most librarians spend most of their time working in one of the following areas of a library:

Public service librarians work at the reference desk. Some specialize in serving adults or children. (In larger libraries they may specialize in teen services, the periodicals or other special collection.)
Technical service librarians work "behind the scenes" ordering library materials and database subscriptions, computers and other equipment, and supervise the cataloguing and physical processing of new books.
Experienced librarians may be promoted to administrative positions such as the library director, or the director of a group of libraries. Similar to the president of any other business, they are concerned with the long-term planning of the library as a business, and its relationship with its parent organization (the city or county for a public library, or the college for an academic library).

See: List of librarians

In the discworld book series by Terry Pratchett there is a librarian who has been magicallyally turned into an orangutan, if you are looking for him; I suggest you check out The Librarian (Discworld).

St. Jerome is the patron saint of librarians and translators.