Reference services help the user define and identify his query correctly, bearing in mind how he intends to use the information, since this can affect the choice of source. The reference personnel then inform him what catalogues, directories, files, secondary publications or databases to consult to seek out the relevant information for himself, explaining, if necessary, how the user should go about his search (direct search). Alternatively, they themselves do the search for the user, if desired so by him i.e. the user (delegated research).
For both these types of searches, reference tools or aids readily available in the library or information unit, may be used. These aids include card files of the library or collections of secondary documents (indexes„ abstracting periodicals, etc.). Often a search may require Use of external information sources some of which cannot be accessed at once An example of such sources is computerised databases which are not accessible online. In such a situation the query is recorded on a prescribed form for conducting searches subsequently and providing the required information.