Bihu, the National Festival of Assam, is celebrated thrice every year. Assam locals celebrate it cheerfully irrespective of beliefs, caste and creed. The Bihu which falls in the middle of April is called the Bohaag Bihu; the one in the middle of January is called the Maagh; and the final one in the middle of October is called the Kaati Bihu.
The Bihus are being celebrated since ancient times in Assam. These essentially mark different seasons, and thereby coincide with the distinct phases of farming. The advent of the seeding time is marked by the Bohaag Bihu, the sowing and transplanting of paddies by the Kaati Bihu, and the end of the harvest by the Maagh Bihu.
Bohaag Bihu, the most enjoyed Bihu, marks the arrival of spring. It is also referred to as the Rongaali Bihu or the Festival of Merriment. It lasts for several days during which the Assam youngsters dress clad in beautiful traditional attires dance in circles while singing folk songs, called Bihu songs. Such gatherings are known as Mukoli bihus.
Now-a-days, Mukoli bihus are replaced in cities and towns by Bihu fairs where they perform Bihu dances on the stage.