Language death occurs when a language is no longer spoken by anyone. Languages do not naturally die out but are instead "killed" when their speakers abandon the language due to pressures to assimilate and adopt dominant languages that have greater social and economic opportunities. There are several types of language death including sudden, radical, gradual, and bottom-to-top death. Major causes of language death include globalization, urbanization, modern education, and the pressure of dominant languages that are given more prestige and power. Efforts can be made to revive languages through programs that promote acquisition by adults, create socially integrated speaker populations, develop literacy in the language, and encourage use of the language in various social domains over time.