First of all this system is not as strict as it used to be, eventough it is still being followed and maintain till now, but it has adapting into the modern life. The Caste system are just a pat of the culture, not to divide the strata of life of the people.
The System are part of the feudal structure before the Indonesian Independence, and all the kingdom in Bali integrated into the Indonesia Government.
The Caste System are divided into 4 which are Brahmana, Ksatria, Waisya, and Sudra . It is also believe that this caste system are derived from the Veda and also a bit similar to those in Indian Society.
The priests leading a ceremony
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One of The Balinese Kings with several knight around
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Waisya
This caste are the main power of the Balinese Economy. They are the merchant who keeps the economy going. This caste are mixed up with the Sudra Caste in the modern life. Because everyone can become a merchant nowadays no matter which caste they are belong to.
Sudra
This is the lowest caste in the Balinese Caste system. Those who falls into this caste are the slave or the common people which has a small influence in the overall system in Bali. Most of the Balinese are falls into this caste, in this modern life they can do any kind of activities or become richer or having a good influence in the modern life.
the modern balinese on the market
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Those caste system later will influence the Language for the Balinese Tribe and also the naming system for Balinese. The Balinese language are also divided into several degree of politeness, and can only be use by and for selected caste.
How about your tribe or country, does it still has the caste system?