The Vaishya caste is the third of the four castes in the Indian caste system.
They are also the last among the three upper castes in the caste system.
As per Hindu religious text, they were formed from the belly of the Hiondu God 'Brahma' and the caste was occupied with farming, agriculture, and trading.
However, as the caste system developed in the Vedic and post-Vedic period,
the Vaishya largely gave up agriculture and turned towards occupations such as merchants, skilled labor and land ownership.
Members of the Vaishya caste have traditionally been wealthy, as a result of their occupations
This caste has given great value to education, particularly religious education so that they would become twice born, an important aspect in the caste system.
Several members of this caste were part of the development of modern Indian industry.
The Global Steel Tycoon Lakshmi Mittal is a Vaishya
Because of their wealth, this caste is heavily involved in religious acitvity and it is generally accepted that the funding for the Hindu fundamentalism in India comes from this caste to a great extent.
This caste is also into charity and philanthropic giving for the benefit of society.
Because the Vaishyas are the lowest among the three upper castes (Brahmin, Kshatriya, Vaishya), their resentment towards it has led to them supporting the spread of non-casteist faiths such as Buddhism and Jainism.
NOTE: You can get very detailed and extensive information about Vaishyas and their role in the caste system in the eBook 'The Truth About Dalits'.