This article offers a detailed description of the relationship between linguistic diversity and biodiversity. For the sake of ease of the presentation the article has been organized into sections, and it deals with, among others, linguistic diversity across the world and in India, respectively. Linguistic landscape in India has been debated with reference to diversity in language and script and features of Indian multilingualism. It also aks why linguistic diversity occurs, how is it evaluated and how languages are lost. Consequences of language loss and concern for language revitalization are debated.