An extinct language is a language that no longer has any first-language or second-language speakers, especially if the language also has no living descendants. In contrast, a dead language is a language that no longer has any first-language speakers, but does have second-language speakers, such as Latin. A dormant language is a dead language that still serves as a symbol of ethnic identity to an ethnic group; these languages are often undergoing a process of revitalisation. Languages that have first-language speakers are known as modern or living languages to contrast them with dead languages, especially in educational contexts.

Yurok is an Algic language. It is the traditional language of the Yurok people of Del Norte County and Humboldt County on the far north coast of California, most of whom now speak English. The last known native speaker died in 2013. As of 2012, Yurok language classes were taught to high school students, and other revitalization efforts were expected to increase the population of speakers.