In the Gregorian calendar, this festival is observed normally in the month of January or February.
As per the legend, once there was an evil asura named Soorapadam who defeated the Devas and started ruling the heaven and the earth.
During this day, there is a National Parade, a speech from the Prime Minister of Singapore and a huge fireworks display.
In this case it is the Solar Month that is looked up for identifying the day of Thai Poosam which falls on Makara in Solar month.
On the Thaipusam day, most devotees of Lord Murugan offer him fruits and flowers of yellow or orange color - his favorite colors and also adorn dresses of the same color.
There but for the grace of God, go I! It is also celebrated in other countries where ethnic Tamils reside such as Canada, Singapore, South Africa, Indonesia, Thailand, Myanmar, Guyana, Suriname, Jamaica, etc.
Supposedly, this symbolises breaking your ego and allowing the purity inside to take hold.
The festival of Thaipusam is celebrated to mark the receiving of spear by Lord Skanda and his victory over the demons.