The use of Welsh can vary by language of household, language of neighbourhood, language of education, language of economic sector, and other factors such as age and social class are crucial.
Gall defnydd o’r Gymraeg amrywio yn ôl iaith aelwyd, iaith cymdogaeth, iaith addysg, iaith sector economaidd ac mae ffactorau eraill megis oedran a dosbarth cymdeithasol yn hollbwysig.