Wikipedia
Chaiwalas are mainly people who prepare, sell or serve Indian tea on streets or small roadside shops. They boil a mixture of water and milk, add tea leaves and then strain the tea into containers or a tea kettle. The expression 'chaiwala' is confined to Northern India.
Many-a-time, the ways for brewing tea are not always very hygienic.
A lot of chaiwala tend to come in from different parts of India and run small businesses in major cities. Chaiwalas usually serve tea in a small glasses or unglazed clay teacups ( Kulhar) but in recent years they have started to serve tea in plastic cups. Traditionally chai was made in brass vessels; however that appears to be changing in some places.
The Indian prime minister Narendra Modi is a former chaiwala. He occasionally used to serve tea to the customers of his father's tea-stall outside the Vadnagar Railway Station. His chaiwala background was mocked by Mani Shankar Aiyar, a senior leader of the then ruling Congress Party. BJP seized on this opportunity to emphasize the humble background of Narendra Modi, by opening a number of "NaMo Teas Stalls" and organizing a public discussion campaign termed "Chai Pe Charcha".
In response, former Chief Minister of Bihar and RJD Chief Lalu Prasad Yadav also claimed to be a former chaiwala.