What are abstracts and indexes?

What are abstracts and indexes? 

Many journals provide an index to their contents, often published at the end of each year. Cumulative indexes are less 

common so, although useful, these annual indexes only include a single year's listings of the contents from one title. If no 

other source were available, the researcher intending to search more widely would be forced to peruse the indexes of all the 

titles of interest, a highly unsatisfactory method of working. To resolve this situation, there are indexing services which 

compile indexes covering large numbers of titles. For example, the Biography Index contains bibliographical information 

from over 3000  journals and  2000 books for individuals and groups in all subjects. Historical Abstracts performs a similar 

function for articles in the subject area of history and includes references from over 2000 journals. There are broad pub-

lications that cover interdisciplinary subjects, such as Scopus which includes life, health, physical, and social sciences and 

IBSS (International Bibliography of the Social Sciences). 

Indexes may provide only the bibliographic details of the articles, while abstracting services also include a summary of the 

article. Confusingly, indexes also  sometimes  contain  abstracts  (see,  for  example,  Index  to  Theses).  The presence of an 

abstract enables the researcher to be more discerning in their selection of articles, as they have a better concept of the 

content. Some collections have been in publication for many years, for example the Chemical  Abstracts  Service (CAS)  has  

indexed  and  summarized  chemistry related articles from many tens of thousands of scientific journals since 1907. in 

addition it provides details of patents, conference proceedings, and other documents pertinent to chemistry, life sciences, 

and other scientific fields. This service, which provides abstracts for more than 27 million documents, is available to 

ubscribers online. Like Chemical Abstracts, many publishers provide an online service with well designed access and search 

options. Performing a search using a printed version is time consuming and can create a complex search trail that the 

researcher must be diligent in managing. An online service allows the researcher to perform keyword searches within the 

text of the abstract and to search other