It is the day for celebration and festivity for Keralites all over the world as they celebrate the colourful harvest festival of Onam from Monday.

Onam is the most celebrated festival in the Indian state of Kerala and marks the annual homecoming of legendary King 'Mahabali', under whose reign Kerala had flourished significantly,as legend states.

Meanwhile, the celebrities from B-town exchanged "Onam" tweets as they join the mood of joy and celebration.

"Happy Onam .. to all my friends in Kerala .. and indeed all over ...love and the best wishes ..," tweeted Big B in his Twitter account "SrBachchan".

The 'Khiladi' girl of Bollywood, Priyanka Chopra, posted: "And happy Onam to all my fellow keralites."

Vivek Oberoi, on the other hand, mentioned about the legend of Onam in his Twitter account "vivek_oberoi" : "Hey tweeps! Today is the first day of Onam. Onam marks the homecoming of the legendary King Mahabali."

Anupam Kher, Malaika Arora Khan, Ritesh Deshmukh and other celebs too wished the nation on this day through 'Twitter'.

The festival of Onam is celebrated for ten long days and the first day, called 'Atham' and the last day named 'Thiruonam', are considered to be the most important of all by the Keralites.

Celebrated in the first month (Chingam) of the Malayam calendar, the festival showcases the best of the Kerala culture and spirit of celebration.

The ten long days of celebration is marked by several exciting events which includes the grand feast called 'Onasadya', prepared on 'Thiruonam', which is a nine course meal consisting of 11 to 13 essential dishes.

Apart from it, the other exciting activities of Onam includes: 'Vallamkali' (the Snake Boat Race which is held on the river Pampa), traditional games named 'Onakalikal' and many more.

Moreover, any festival is incomplete without food and dishes and Onam is no exception.

During these ten days the Keralites prepare several traditional dishes like Avial, Banana Halwa, Dry Fruit Kesari, Coconut Chutney, Dosas and many more stuffs to add to the mood of festivity.

Truly, India is a land of diverse culture and festivity and these occasions highlights the spirit and vibrancy of Indian states.