[8] At the behest of Joseph Cogswell, John Jacob Astor placed a codicil in his will to bequeath $400,000 (equivalent of $14.1 million in 2024) for the creation of a public library.

Bibliophile and philanthropist James Lenox donated a vast collection of his Americana, art works, manuscripts, and rare books,[16] including the first Gutenberg Bible in the New World.

[12] This money would sit untouched in a trust for several years, until John Bigelow, a New York attorney, and Andrew Haswell Green, both trustees of the Tilden fortune, came up with an idea to merge two of the city's largest libraries.

Although New York City already had numerous libraries in the 19th century, almost all of them were privately funded and many charged admission or usage fees (a notable exception was Cooper Union, which opened its free reading room to the public in 1859).

On May 23, 1895, Bigelow, Cadwalader, and George L. Rives agreed to create "The New York Public Library, Astor, Lenox and Tilden Foundations".

The trustees hired McKim, Mead & White, Carrère and Hastings, and Walter Cook to design all the branch libraries.

[29] The directors in turn reported to an elite board of trustees, chiefly elderly, well-educated, philanthropic, predominantly Protestant, upper-class white men with commanding positions in American society.

[30] Representative of many major board decisions was the purchase in 1931 of the private library of Grand Duke Vladimir Alexandrovich (1847–1909), uncle of the last tsar.

This was one of the largest acquisitions of Russian books and photographic materials; at the time, the Soviet government had a policy of selling its cultural collections abroad for gold.

[32] The military drew extensively from the library's map and book collections in the world wars, including hiring its staff.

For example, the Map Division's chief Walter Ristow was appointed as head of the geography section of the War Department's New York Office of Military Intelligence from 1942 to 1945.

Ristow and his staff discovered, copied, and loaned thousands of strategic, rare or unique maps to war agencies in need of information not available through other sources.

[33] The organizers of the New York Public Library, wanting an imposing main branch, chose a central site along Fifth Avenue between 40th and 42nd Streets, on top of the Croton Reservoir.

[40] Today, the branch's main reading room is equipped with computers with access to library collections and the Internet as well as docking facilities for laptops.

A Fellows program makes reserved rooms available for writers and scholars, selected annually, and many have accomplished important research and writing at the library.

[44] In the 1990s, the New York Public Library decided to relocate that portion of the research collection devoted to science, technology, and business to a new location.

The SIBL, with approximately two million volumes and 60,000 periodicals, is the nation's largest public library devoted solely to science and business.

[46] In 2010, as part of the consolidation program, the NYPL moved various back-office operations to a new Library Services Center building in Long Island City.

In 2014 NYPL launched a project called "Library Simplified", to address the difficulties that patrons were having checking out e-books, especially compared to the process for buying them.

[47] By 2016 the project had produced an app called "SimplyE", which the library launched that year; patrons could explore and check-out ebooks from multiple vendors, with just a few clicks.

[63] Before this facility opened, all the aforementioned departments were housed in different locations with no accountability between them, and items sometimes taking up to two weeks to reach their intended destination.

[65] The consolidations and changes in collections have promoted continuing debate and controversy since 2004 when David Ferriero was named the Andrew W. Mellon Director and Chief Executive of the Research Libraries.

The NYPL gives cardholders free access from home to thousands of current and historical magazines, newspapers, journals and reference books in subscription databases, including EBSCOhost, which contains full text of major magazines; full text of the New York Times (1995–present), Gale's Ready Reference Shelf which includes the Encyclopedia of Associations and periodical indexes, Books in Print;[86] and Ulrich's Periodicals Directory.

The New York Public Library also links to outside resources, such as the Bureau of Labor Statistics' Occupational Outlook Handbook, and the CIA's World Factbook.

The Digital Collections was named one of Time Magazine's 50 Coolest Websites of 2005[89] and Best Research Site of 2006 by an international panel of museum professionals.

[97] The Oral History Project includes people living in Greenwich Village, Harlem, Washington Heights and Inwood, Times Square, Hell's Kitchen, Soho, Lower East Side, Chinatown, and Kips Bay as well as Transgender, Latino Americans, Veterans, and Disability Experience.

An initiative was taken in July 2018, NYC library card holders are allowed to visit Whitney Museum, the Guggenheim and 31 other prominent New York cultural institutions for free.

[103] The basic powers and duties of all library boards of trustees are defined in the Education Law and are subject to Part 90 of Title 8 of the New York Codes, Rules and Regulations.

[103] The NYPL's charter, as restated and granted in 1975, gives the name of the corporation as The New York Public Library, Astor, Lenox and Tilden Foundations.

[108] Along with Harvard, Columbia, and Princeton, NYPL is a member of the Research Collections and Preservation Consortium (ReCAP), and shares an off-site shelving facility in Plainsboro, New Jersey with the three Ivy League universities.