Kaarthigai Deepam is a festival related to lights, celebrated in the Tamil month of Kaarthigai. It is celebrated on the full moon day of the Kaarthigai month which coincides with Krithikai star. It is also considered as the extension of the Deepavali festival.
The popular legend behind the celebrations is that once the Devas (Gods), wants to have a complete darshan of Lord Shiva. Lord Shiva asked Brahma and Vishnu to find out the exact location of his head and his feet. Since Lord Shiva took a gigantic form, they were not able to find him anywhere. After that Lord Shiva appeared before them in the form of light whose ends cannot be defined on the hill of Thiruvannamalai. Therefore, Kaarthigai Deepam is also known as Annamalai Deepam.
On Karthigai day evening people draw kolams (rangoli) in the front of the house and also place lamps (Agal) around it. After deeparathana(a religious ritual) and move the lamps to different places in the house.
http://tamilnadu.south-india-tourism.com/festivals-of-tamilnadu/karthigai-deepam.html
[Source indiatastes.com (43) 10-Jun-04]
