Ganesha Chaturthi (गणेश चतुर्थी) is the Hindu festival celebrated in honor of the god Ganesha, remover of obstacles, and the god of beginnings and wisdom. is observed in the Hindu calendar month of Bhaadrapada, starting on the shukla chaturthi (fourth day of the waxing moon period). The date usually falls between 19 August and 20 September.
The festival involves installing clay images of Ganesha in public pandals (temporary shrines), which are worshipped for ten days with different variety of herbal leaves, plants and immersed at the end of the festival in a water(lake) along with the Idol. After adding herbal and medicated plants and leaves(patri) in lakes, the water in the lake becomes purified. This was in practice because, in early days people used to drink lake water, and to protect people with infections and viral diseases especially in this season, this tradition was introduced. Some Hindus also install the clay images of Ganesha in their homes. It is believed that Ganesha bestows his presence on earth for all his devotees during this festival.
Traditional Ganesha Hindu stories tell of Lord Ganesha, son of goddess Parvati, who is consort of Shiva. Parvati created Ganesha out of sandalwood paste that she used for her bath and breathed life into the figure. She then set him to stand guard at her door while she bathed. Lord Shiva, who had gone out, returned and as Ganesha didn't know him, didn't allow him to enter. Lord Shiva became enraged by this and asked his follower Ganas to teach the child some manners. Ganesha who was very powerful, being born of Parvati, the embodiment of Shakti, defeated Shiva's followers and declared that nobody was allowed to enter while his mother was bathing.
The sage of heavens, Narada along with the Saptarishis sensed the growing turmoil and went to appease the boy with no results. Angered, the king of Gods, Indra attacked the boy with his entire heavenly army but even they didn't stand a chance. By then, this issue had become a matter of pride for Parvati and Shiva. Angry Shiva severed the head of the child. Parvati seeing this became enraged. Seeing Parvati in anger Shiva promised that her son will be alive again. The devas searched for the head of dead person facing North, but they found only the head of a dead elephant. They brought the head of the elephant and Shiva fixed it on the child's body and brought him back to life. Lord Shiva also declared that from this day the boy would be called Ganesha (Gana Isha : Lord of Ganas).