Citation indexing is unique as a retrieval system because it is a network of connections between authors citing the same papers during a given year. Citation indexes are the only indexes that allow you to search forward through the literature in a particular year in a specific subject area. For example, if you have a research article in hand and you want to know what research has built upon it, or whether any research has refuted it, you can use citation indexing to trace this path through time.
Coverage is from acoustics and aeronautics to surgery and zoology.
Not only are scientific topics covered in full, many related areas are covered as well. Over 3000 journals are indexed in depth. About 250 books are noted. Coverage is of the complete social sciences from anthropology to urban planning and development. The SSCI is particularly useful for questions on community problems and business and statistical questions.