Ganesh Chaturthi, Vinayaka Chavithi, is one of the biggest festivals in Hinduism is celebrated on the fourth day of bright fortnight in Bhadrapad Month in Hindu calendar (Shukla Paksha Chaturthi in Bhadrapada Masam). In 2013, Ganesh Chaturthi date is September 9, Monday.
Ganesh Chaturthi is also celebrated as Ganesh Navratri for more than 9 days, starting from Ganesh Chaturthi festival till Anant Chaturdasi.
On the last day, Ganesha idols that are worshipped during Ganpati festival are immersed in water (Ganesh Visarjan / Ganapathi Nimmajjanam).
Ganesh Chaturthi is celebrated with utmost gusto and fervor in Mumbai, Pune, Nagpur, Thane, Solapur and other cities of Maharashtra, Hyderabad, Visakhapatnam (Vizag), Vijayawada, Nizamabad, Warangal, Karimnagar, and many other places of Andhra Pradesh, Bangalore, Mysore, Mangalore, and some more towns in Karnataka, Surat, Ahmedabad, Vadodara and many places in Gujarat, and most of other North Indian states.
Lord Ganesha is also referred to as Vinayaka, Vighneshwara, Vinayagar, Pillaiyar, Ganapathi, etc…