The subject bibliographies form the largest group of enumerative bibliographies. It is defined as the one that deals with the materials pertaining to a single given subject which may be a place (for example United States), a person (Pandit Jawaharlal Nehru), a broad subject (Social Sciences, Computer Science) or a smaller branch of any subject ( Solid State Physics), a thing ( Computers). Ranganathan defined a subject bibliography as the one that is a document bibliography confined to a specific subject field, instead of covering the entire universe of subjects.
The subject bibliographies may occur as independent publications or parts of documents. They will have a limited scope with regard to form of material, time span, sources of origin and language. They are usually either selective or comprehensive and may be current or retrospective. Depending on the contents of subject bibliographies, they can be divided into various categories.