Indian family names are based on a variety of systems and naming conventions, which vary from region to region. Names are also influenced by religion and caste and may come from epics. India's population speaks a wide variety of languages and nearly every major religion in the world has a following in India. This variety makes for subtle, often confusing, differences in names and naming styles. For example, the concept of a family name did not exist widely in Tamil Nadu.
For many Indians, their birth name is different from their official name; the birth name starts with a letter auspicious on the basis of the person's horoscope (based on the nakshatra or lunar mansion corresponding to the person's birth).
In communities that don't use family names, the third name can be a god's name, or the grandfather's or grandmother's name, depending on the sex of the child. Many children are given two names, sometimes as a part of religious teaching.