The Red Data Book, also known as the Red List, is a comprehensive record of species that are categorised as threatened, endangered, or vulnerable to extinction. It is compiled and periodically updated by the International Union for Conservation of Nature (IUCN), a global organization dedicated to assessing the conservation status of species and ecosystems.

The primary purpose of the Red Data Book is to provide authoritative information on the conservation status of species, serving as a valuable resource for conservationists, policymakers, researchers, and the general public. It helps identify species at risk of extinction, prioritize conservation efforts, and inform decision-making processes related to biodiversity conservation and management.

The Red Data Book classifies species into different categories based on the level of threat they face. These categories include:

Extinct(EX): Species that are believed to have become extinct, with no known individuals remaining.

Extinct in the wild(EW): Species that survive only in captivity or cultivation, with no known populations remaining in their natural habitat.

Critically Endangered(CR): Species facing an extremely high risk of extinction in the wild, with very small populations and severe declines in numbers or range.

Endangered(EN): Species facing a very high risk of extinction in the wild, with significant declines in population size or range.

Vulnerable (VU): Species facing a high risk of extinction in the wild, with moderate declines in population size or range.

Near Threatened(NT): Species that are close to qualifying for a threatened category but do not currently meet the criteria.

Least Concern(LC) : Species that are not currently considered threatened with extinction, with widespread and abundant populations.

Data Deficient(DD)  : Species for which there is insufficient information to assess their conservation status accurately.

The Red Data Book provides detailed assessments for thousands of species across various taxonomic groups, including mammals, birds, reptiles, amphibians, fishes, invertebrates, plants, and fungi. It plays a critical role in guiding conservation efforts, raising awareness about the plight of threatened species, and mobilizing support for their protection and recovery.