Despite its small population, Laos has 49 ethnic groups, or tribes, from which Lao, Khmou and Hmong constitute approximately three-quarters of the population. Most tribes are small, with some having just a few hundred members. The ethnic groups are divided into four linguistic branches: Lao-Tai language represented by 8 tribes, Mone-Khmer language with 32 tribes, Hmoung-Loumien language with 2 tribes and Tibeto-Chinese language represented by 7 tribes.
Laos is officially Buddhist, and the national symbol, the gilded stupa of Pha That Luang, has replaced the hammer and sickle even on the state seal. Still, there is a good deal of animism mixed in, particularly in the baci (also baasi) ceremony conducted to bind the 32 guardian spirits to the participant's body before a long journey, after serious illness, the birth of a baby or other significant events.
Lao custom dictates that women must wear the distinctive phaa sin, a long sarong available in many regional patterns; however, many ethnic minorities have their own clothing styles. The conical Vietnamese-style hat is also a common sight. These days men dress Western-style and only don the phaa biang sash on ceremonial occasions. Nowadays women often wear Western-style clothing, though the "phaa sin" is still the mandatory attire in government offices (not only for those who work there, but also for Lao women just visiting).