Navarathri - The nine day(night) festival for Devi.
Navratri that is celebrted as the beginning of winter is also known as Maha Navratri or Sharada Navartri. The festival falls on the Purattasi or Ashwin month. Starting on the new moon day and ends on the 10th day.
This is one another festival, after Diwali, which is celebrated by almost by all, all over India. Nava - nine, Ratri - night.
Devi is worshipped in her 3 important forms - Durga, Lakshmi and Saraswathi. The first 3 days are for Durga, the middle 3 days are for lakshmi and the last 3 days are for Saraswati and the 10th day Vijayadasami is celebrated to proclaim victory. On the 9th day or on the Navami day, the books and the equipments used to do business are kept in Pooja and lordess Saraswathi is worshipped on that day. On the Vijayadasami day, the small kids who are yet to go to school are taken to the school and Aksharabyasam is started.
Durga is the personification of Shakti or power or energy. She is the destroyer of evil and she is the consort of Lord Shiva.
Lakshmi is the personification of wealth and she is the consort of Mahavishnu.
Saraswathi is the personification of knowledge and she is the consort of Brahma.
This year Navarathri starts on 18th September and Vijayadasami is on 28th September.