b. A group with a shared ancestry or shared cultural heritage - While the word 'race' refers to differences in physical appearance that are of social importance, the word 'ethnicity' refers to differences based on the culture and heritage. In other words, people who share common ancestors, culture, values and beliefs belong to the same ethnic group. For example, Bangladesh has a number of ethnic groups like Bengalis, Chakmas, Garos, Marmas, etc. The people belonging to these groups speak their own languages, have their own cultures as well as social systems. For example, the Chakmas have a matriarchal social system, where the women are the dominant members of the families.