Harvard University (incorporated as The President and Fellows of Harvard College) is a private university in Cambridge, Massachusetts, U.S., and a member of the Ivy League. Founded in 1636 by the colonial Massachusetts legislature,op. cit. Harvard is the oldest institution of higher learning in the United States. It is also the first and oldest corporation in North America.

Initially called "New College" or "the college at New Towne", the institution was named Harvard College on March 13, 1639, after a young clergyman named John Harvard—a graduate of England's Emmanuel College, Cambridge (a college of the University of Cambridge) and St Olave's Grammar School, Orpington in the United Kingdom—who bequeathed the College his library of four hundred books and £779 (which was half of his estate). The earliest known official reference to Harvard as a "university" occurs in the new Massachusetts Constitution of 1780.

During his 40-year tenure as Harvard president (1869–1909), Charles William Eliot radically transformed Harvard into the pattern of the modern research university. Eliot's reforms included elective courses, small classes, and entrance examinations. The Harvard model influenced American education nationally, at both college and secondary levels. Eliot also was responsible for publication of the now-famous "Harvard Classics", a collection of "great books" from multiple disciplines, published by P. F. Collier and Sons beginning in 1909, that offered a college education "in fifteen minutes a day of reading." The collection soon became known as "Dr. Eliot's Five-Foot Shelf." During his unprecedentedly influential presidency, Eliot, a prolific book and magazine writer and widely traveled speaker in the pre-radio age, became so widely recognized a public figure that by his death in 1926, his name (and, not coincidentally, Harvard's) had become synonymous with the universal aspirations of American higher education.

In 1999, Radcliffe College, founded in 1879 as the "Harvard Annex for Women", merged formally with Harvard University, becoming the Radcliffe Institute for Advanced Study.

Harvard's library collection contains more than 15 million volumes,See the FAQ on the Harvard-Google partnership. making it the largest academic library in the United States, and the fourth among the five "mega-libraries" of the world (after the Library of Congress, the British Library, and the French Bibliothèque nationale, but ahead of the New York Public Library). See the ranked list of U.S. libraries from the American Library Association. Harvard is consistently ranked number one in international college and university rankings, and has the largest financial endowment of any non-profit organization except for the Bill & Melinda Gates Foundation, standing at $38.7 billion as of 2008.