This document discusses sources for researching British ancestry, including census records, parish records, genealogy websites, and original birth, marriage, and death records. It emphasizes that original records are most reliable, while derivative records such as indexes and transcriptions introduce more chances for errors. The document recommends using both local register office indexes, which are closer to the original records, and national indexes from the GRO for their wider coverage of records as ancestors moved around. It also describes the UKBMD project which has brought online indexes from several British regions by working with local register offices and family history societies.