Subject indexes and abstracting services
Searching of documents on a particular aspect of a subject can be a very time consuming effort if a large number of scattered references are to be gathered together. A helpful scanning of literature can be carried out by searching from the indexes of books and periodicals. There are also serials available, known as indexing services, which include all details of the published documents in a helpful sequence. In some cases, the entries also include summaries of the texts, these are known as the abstracting services.
Most of the periodicals of reference value usually have their own indexes (when record of all the articles that appear in a periodical and are usually appended to a full volume of a periodical). Cumulated indexes, e.g., ten-year or five year cumulations are also available in various cases. Nowadays, computerised indexes on microfiche are also available.
The indexing and abstracting services have great importance for users searching documents for current and retrospective search of literature. The indexing services are usually an author-subject index of books, periodical articles, pamphlets, theses or any other media on any particular subject. On the other hand, the abstracting services have some kind of classified or subject arrangement wherein the entries under a subject are arranged author-wise with all the bibliographic details and an abstract of the original text. The categorized part is supported by author, title and subject indexes for searching.
Citation indexes, another type of indexes, enable a researcher who has details of one reference to a subject in which he is interested, to discover other references connected to it or cited which have been published later. The first such index to be published was Science Citation Index, Philadelphia : ISI 1961-. The cifotein midexes on Social Science and Arts & Humanities and also publication by ISI.
Serial lists of the contents of the latest issues of the leading periodicals on a particular subject are a recent addition to the bibliographies which control periodical literature. The best known of this is the one published by the Institute for Scientific Information. U.S.A., that is, Current Contents Life Sciences, 1961-. There are other series also on different subjects.
Current awareness bulletins, especially prepared by special libraries also help their users by presenting the lists of new periodical articles, either as subject lists or as contents lists. They can also comprise lists of new books added to the library.