Dear student,
IUCN Red Data Book is also called IUCN Red List is a book which is published by the IUCN (International union for conservation of nature and natural resources). It contains the list of organisms whose continued survival in the present state is threatened. It contains the names of all species which are threatened and classified under various categories like threatened, endangered etc. Red list is prepared so that there should be a record of all endangered flora and fauna and thus proper steps could be taken to protect them. These are different for plants and animals.
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