It is a known fact that an encyclopedia provides comprehensive information on many aspects of one subject or on many subjects. While a glossary or a definitional dictionary gives a short definition or explanation of a term, an encyclopedia gives a more information on the concerned term. Encyclopedias are needed for the learners of technical subjects.  There are no encyclopedias in Hindi on subjects relating to Science and Technology. For students and teachers using Hindi as a medium of instructions, encyclopedias will be of immense help. The Commission has taken up the task of preparing encyclopedias in Hindi on subject relating to science and technology.