All languages undergo natural systematic change.
Sufficient changes may result in separate languages that share an ancestral form. There are over 6700 distinct languages in the world today. Language surveys can be designed to ascertain linguistic relationships, degree of intelligibility between language varieties, language attitudes, degree of bilingualism, etc. Language survey is still needed throughout the world to help determine where Scripture translation is still needed. In a real sense, each speaker of a language may be said to have his or her own variety of the language.