This article is from the Libraries FAQ, by Anthony Wilson firstname.lastname@example.org with numerous contributions by others.
The ALA Glossary defines it as
"The knowledge, demands and skills by which recorded information is
selected, acquired, organized and utilized in meeting the information
needs of a community of users."(pg. 132) However, Will Manley writes,
"library science is an oxymoron. There is absolutely nothing
scientific about librarianship." (pg. 175)