In this paper the characteristics and sources of data for bibliometric studies are reviewed. Most of the sources of data for bibliometric studies comes from references, bibliographies, citations and patent literature, etc. The characteristics of bibliometric studies usually includes countries, forms and languages of publication, literature obsolescence, author distribution and extent of scatter of the literature. Two basic bibliometric laws, Bradford's' and Lotka's, have been discussed in detail. The former describes the distribution of periodical articles within a specific discip1ine and can be used to determine the core journals. The latter describes the distribution of authors' productivity.