A librarian is a person who works professionally in a library, providing access to information and sometimes social or technical programming to users. In addition, librarians provide instruction on information literacy to users.

Duties and functions

Traditionally, a librarian is associated with collections of books, as demonstrated by the etymology of the word "librarian". The role of a librarian is continually evolving to meet social and technological needs. A modern librarian may deal with provision and maintenance of information in many formats, including: books; electronic resources; magazines; newspapers; audio and video recordings; maps; manuscripts; photographs and other graphic material; bibliographic databases; and web-based and digital resources. A librarian may also provide other information services, including: information literacy instruction; computer provision and training; coordination with community groups to host public programs; assistive technology for people with disabilities; and assistance locating community resources. Appreciation for librarians is often included by authors and scholars in the acknowledgment sections of books.


The ancient world

The Sumerians were the first to train clerks to keep records of accounts. "Masters of the books" or "Keepers of the Tablets" were scribes or priests who were trained to handle the vast amount and complexity of these records. The extent of their specific duties is unknown.
Sometime in the 8th century BC, Ashurbanipal, King of Assyria, created a library at his palace in Nineveh in Mesopotamia. Ashurbanipal was the first individual in history to introduce librarianship as a profession. We know of at least one "keeper of the books" who was employed to oversee the thousands of tablets on Sumerian and Babylonian materials, including literary texts; history; omens; astronomical calculations; mathematical tables; grammatical and linguistic tables; dictionaries; and commercial records and laws. All of these tablets were cataloged and arranged in logical order by subject or type, each having an identification tag.
The Great Library of Alexandria, created by Ptolemy I after the death of Alexander the Great in 323 BC, was created to house the entirety of Greek literature. It was notable for its famous librarians: Demetrius, Zenodotus, Eratosthenes, Apollonius, Aristophanes, Aristarchus, and Callimachus. These scholars contributed significantly to the collection and cataloging of the wide variety of scrolls in the library's collection. Most notably, Callimachus created what is considered to be the first subject catalogue of the library holdings, called the pinakes. The pinakes contained 120 scrolls arranged into ten subject classes; each class was then subdivided, listing authors alphabetically by titles. The librarians at Alexandria were considered the "custodians of learning".
Near the end of the Roman Republic and the beginning of the Roman Empire, it was common for Roman aristocrats to hold private libraries in their home. Many of these aristocrats, such as Cicero, kept the contents of their private libraries to themselves, only boasting of the enormity of his collection. Others, such as Lucullus, took on the role of lending librarian by sharing scrolls in their collection. Many Roman emperors included public libraries into their political propaganda to win favor from citizens. While scholars were employed in librarian roles in the various emperors' libraries, there was no specific office or role that qualified an individual to be a librarian. For example, Pompeius Macer, the first librarian of Augustus' library, was a praetor, an office that combined both military and judicial duties. A later librarian of the same library was Gaius Julius Hyginus, a grammarian.

Middle Ages and Renaissance

Christian monasteries in Europe are credited with keeping the institution of libraries alive after the fall of the Roman Empire. It is during this time that the first codex enters popularity: the parchment codex. Within the monasteries, the role of librarian was often filled by an overseer of the scriptorium where monks would copy out books cover to cover. A monk named Anastasias who took on the title of Bibliothecarius following his successful translations of the Greek classicists. During this period, the lectern system, in which books were chained to desks for security, was also introduced. Classification and organization of books during this period was generally done by subject and alphabetically, with materials inventoried using basic check lists. Later in the period, individuals known as librarius began more formal cataloguing, inventory, and classification.
In the 14th century, universities began to reemerge which had libraries and employed librarians. At the same time royalty, nobles and jurists began to establish libraries of their own as status symbols. King Charles V of France began his own library, and he kept his collection as a bibliophile, an attribute that is closely connected to librarians of this time.
The Renaissance is considered to be a time of aristocratic enthusiasm for libraries. During this period, great private libraries were developed in Europe by figures such as Petrarch and Boccaccio. These libraries were sponsored by popes, royals, and nobility who sent agents throughout Western Europe to locate manuscripts in deteriorating monastic libraries. As a result, Renaissance libraries were filled with a wealth of texts. While materials in these libraries were mostly restricted, the libraries were open to the public. Librarians were needed to plan and organize libraries to meet public needs. A tool to achieve these organizational goals, the first library catalog, appeared in 1595.

Enlightenment era

, National Museum in Warsaw
During the 16th century, the idea of creating a Bibliotheca Universalis, a universal listing of all printed books, emerged from well-established academics and librarians: Conrad Gessner, Gabriel Naudé, John Dury, and Gottfried Leibniz. The four librarians responsible for establishing the Bibliotheca Universalis are important figures in librarianship. Gabriel Naude published Avis pour dresser une bibliothèque, the first printed monograph on librarianship. In this monograph, Naude advocated collecting all kinds of books, old and new, of famous, more obscure, and heretical authors. He also contributed to the idea of organization and administration of libraries which led to the development of library collections. It was also in part thanks to Naude that some libraries began to lend books outside of the precincts of the library.
John Dury is considered to be the first English library theorist. He wrote two letters to Samuel Hartlib concerning the duties of a professional librarian, which were published in 1650 as "The Reformed Librarie-Keeper". He held that librarians should not only care for the books, but should also be well educated and accomplished to raise the standards of librarianship. Furthermore, he advocated that librarians deserve a living wage in order to use their energy to perform their duties to the fullest extent. Gottfried Leibniz upheld that the librarian was the most important factor in the aid of learning. He is credited as including science texts in addition to conventional literature within library collections.
Another key figure of this time was Sir Thomas Bodley, who gave up his career as a diplomat and established Oxford's Bodleian library. He is credited as creating the first functional library of modern times. Subsequent librarians following Bodley were called Protobibliothecarius Bodleianus, Bodley's Librarian. They would earn £40 a year. The ideas formed with these librarians continued to develop into the 17th century. With the approach of Bibliotheca Universalis, libraries changed; the content of libraries became less selective, to include literature of entertainment as well as academic value. At this time, libraries also became fully open to the public, with access no longer restricted to a small circle of readers.
In 18th-century France, two librarians, Hubert-Pascal Ameilhon and Joseph Van Praet, selected and identified over 300,000 books and manuscripts that became the property of the people in the Bibliothèque Nationale. During the French Revolution, librarians assumed sole responsibility for selecting books for use by all citizen of the nation. Out of this action came the implementation of the concept of modern library service: the democratic extension of library services to the general public, regardless of wealth or education.

Modern era

While there were full-time librarians in the 18th century, the professionalization of the library role was a 19th-century development, as shown by its first training school, its first university school, and its first professional associations and licensing procedures. In England in the 1870s, a new employment role opened for women in libraries; it was said that the tasks were "Eminently Suited to Girls and Women." By 1920, women and men were equally numerous in the library profession, but women pulled ahead by 1930 and comprised 80% by 1960. The factors accounting for the transition included the demographic losses of the First World War, the provisions of the Public Libraries Act of 1919, the library-building activity of the Carnegie United Kingdom Trust, and the library employment advocacy of the Central Bureau for the Employment of Women. In the United Kingdom, evidence suggests that the Conservative government began replacing professional librarians with unpaid volunteers in 2015–2016.

Roles and responsibilities

, 1946===Positions and duties===
Specific duties vary depending on the size and type of library. Olivia Crosby described librarians as "Information experts in the information age". Most librarians spend their time working in one of the following areas of a library:
Archivists can be specialized librarians who deal with archival materials, such as manuscripts, documents and records, though this varies from country to country, and there are other routes to the archival profession.
Collection development or acquisitions librarians monitor the selection of books and electronic resources. Large libraries often use approval plans, which involve the librarian for a specific subject creating a profile that allows publishers to send relevant books to the library without any additional vetting. Librarians can then see those books when they arrive and decide if they will become part of the collection or not. All collections librarians also have a certain amount of funding to allow them to purchase books and materials that don't arrive via approval.
Electronic resources librarians manage the databases that libraries license from third-party vendors.
School librarians work in school libraries and perform duties as teachers, information technology specialists, and advocates for literacy.
Instruction librarians teach information literacy skills in face-to-face classes or through the creation of online learning objects. They instruct library users on how to find, evaluate, and use information effectively. They are most common in academic libraries.
Media specialists teach students to find and analyze information, purchase books and other resources for the school library, supervise library assistants, and are responsible for all aspects of running the library/media center. Both library media teachers and young adult public librarians order books and other materials that will interest their young adult patrons. They also must help YAs find relevant and authoritative Internet resources. Helping this age group to become lifelong learners and readers is a main objective of professionals in this library specialty.
Outreach librarians are charged with providing library and information services for underrepresented groups, such as people with disabilities, low income neighborhoods, home bound adults and seniors, incarcerated and ex-offenders, and homeless and rural communities. In academic libraries, outreach librarians might focus on high school students, transfer students, first-generation college students, and minorities.
Public service librarians work with the public, frequently at the reference desk of lending libraries. Some specialize in serving adults or children. Children's librarians provide appropriate material for children at all age levels, include pre-readers, conduct specialized programs and work with the children to help foster interest and competence in the young reader.
Reference or research librarians help people doing research to find the information they need, through a structured conversation called a reference interview. The help may take the form of research on a specific question, providing direction on the use of databases and other electronic information resources; obtaining specialized materials from other sources; or providing access to and care of delicate or expensive materials. These services are sometimes provided by other library staff that have been given a certain amount of special training; some have criticized this trend.
Systems librarians develop, troubleshoot and maintain library systems, including the library catalog and related systems.
Technical service librarians work "behind the scenes" ordering library materials and database subscriptions, computers and other equipment, and supervise the cataloging and physical processing of new materials.
A Youth Services librarian, or children's librarian, is in charge of serving young patrons from infancy all the way to young adulthood. Their duties vary, from planning summer reading programs to weekly story hour programs. They are multitaskers, as the children's section of a library may act as its own separate library within the same building. Children's librarians must be knowledgeable of popular books for school-aged children and other library items, such as e-books and audiobooks. They are charged with the task of creating a safe and fun learning environment outside of school and the home.
A young adult or YA librarian specifically serves patrons who are between 12 and 18 years old. Young adults are those patrons that look to library services to give them direction and guidance toward recreation, education, and emancipation. A young adult librarian could work in several different institutions; one might be a school library/media teacher, a member of a public library team, or a librarian in a penal institution. Licensing for library/media teacher includes a Bachelor or Master of Arts in Teaching and additional higher-level course work in library science. YA librarians who work in public libraries are expected to have a master's degree in Library and Information Science, relevant work experience, or a related credential.