First, following the introduction of definitions of “information”, characteristics of information theory are reviewed with references to recording and communication. Shannon's theory is paid special attention as it is thought it sent a new idea into library science.
Secondly, library techniques to handle sources of information are discussed. The development of bibliographies is examined in detail since they have played a very important role, together with abstracting journals, to have access to information sources.
Thirdly, the relation between documentation and library science is observed by putting a facus upon Shera and Bradford. In the latter part, the duties of documentalists are considered in comparison with those of librarians.
In the fourth part, sources of information and information theory are taken as the object of study. The ever increasing sources can largely be controled by the adaptation of mechanical method. Gulls’ theory is discussed here fully.
As the conclusion, the writer suggests the followings to the Japanese library world: (1) Documentation technique has to be adapted cleverly to library science, (2) Documentation has to be extended to humanities, (3) Librarians have to keep themselves abreast with recent inventions, (4) Research method has to be developed, (5) It is necessary to encourage the communication of sources of information, (6) Training of staff is of special importance.
