This book gives an idea about the production of hydrogen gas in a combined way of biotechnology and chemical technology.This idea adds some idea to the old routine models of study.Still some new modifications are in need to be added to this work. This may help scientist to apply some new knowledge and renovate this work in a useful way. Here many hydrogen producing bacteria are presented and the mode of mechanism is explained, the work we carried out is explained still advancement is needed to be added here.This is new emphasis of hydrogen production as in future it is in need to meet the...