- MLS - Master of Library Science (the traditional degree name)
- MLIS - Master of Library and Information Science
- MLISc - Master of Library and Information Science
- MIS - Master of Information Science
- MSLIS - Master of Science in Library and Information Science
Most degrees from library schools are variations on the above. Several school names themselves have changed, often to diminish or eliminate the word "library" and emphasize some form of "Information Studies." Presumably relating to the poor image of librarians, the purpose and effects of such name changes are debatable.
Some schools offer undergraduate and associates degrees or concentrations in library science. However employment in most professional library positions requires a masters degree from an ALA-accredited institution. Doctoral programs in library science draw limited enrollment, usually from those interested in library management or becoming library school faculty.
Just as all hospital employees are not doctors, people without library degrees who work in libraries (such as paraprofessionals) are usually not called librarians. Some faculty and subject-specialist positions require a second master's degree. However not everyone follows this naming convention. For example, in his failed 2002 senate campaign, Doug Forrester -- a former library student worker -- ran an ad in which he stated, "I flipped burgers, I was a librarian," much to the consternation of librarians (and, for that matter, burger flippers).