Several legends explain how Ganesh/Ganpati got an elephant’s head. The most popular one tells that his mother Parvati created him out of the sandalwood paste on her body and of the river Ganges. Then she told him to guard her bathroom while she bathed.
Lord Shiva, Parvati’s husband, had been away and when he returned he did not recognize his son and was angry at Ganesh for keeping him away from his wife. As a result, Shiva struck off Ganesh’s head.
Parvati became devastated. To comfort her, Shiva promised to restore Ganesh to life. He told his attendants to bring him the head of any sleeping being they found who was facing north. In a while, the attendants returned with an elephant head which Lord Shiva affixed to Ganesh.
Parvati was not consoled. She told Shiva that no one would respect her son with a big elephant head on his shoulders. So Lord Shiva promised that all worshippers would forever pray to Ganpati before praying to God and would invoke Ganpati’s blessings before beginning any important undertaking in life.
In this manner, Ganpati became the leader of the people, the lord of success, the remover of obstacles, and the destroyer of evil. He is honored in most Hindu homes and establishments and people celebrate him every year in a big ten-day-long festival held in August or September. True to Shiva’s word, Ganpati has become a part of every Hindu’s life.