Information on the ancestry, languages, and literacy of the U.S. population based on data collected by the Bureau of the Census in 1979 is reported. Items surveyed include ancestry, country of birth of the individual and parents, citizenship, year of immigration, native language, language spoken in the home, ability to speak English, and ability to read and write any language. Eleven tables provide data on 49 ancestry groups by age and sex; selected social and economic characteristics of ancestry groups; language use and ability by age group; and literacy by age, race, nativity, and parentage. Appendices provide definitions and a discussion of the source and reliability of estimates. (RW)