For the first time, India’s 100 richest people are all billionaires, with a combined wealth of more than $386 billion. They made their fortunes from an array of industries, including steel, pharmaceuticals, oil and gas and even diamonds.

Below are six Indian billionaires to know:

1.       Chair of Mumbai-based oil, gas and manufacturing conglomerate Reliance Industries, Mukesh Ambani (57), topped the list with $23.6 billion in net worth. Ambani’s father, Dhirubhai Ambani, co-founded Reliance Industries with his cousin, Champaklal Damani, in the 1960s, and it has since become the country’s second-largest publicly traded company following the state-run Indian Oil Corporation. While only four women made the richest 100 list, Ambani’s wife, Nita (50), became the first woman director on Reliance’s 14-member board in June. Mukesh Ambani is credited with pioneering India’s entry into overseas capital markets and has reduced telephone costs in more than 600 cities. He got his bachelor of chemical engineering degree from the University of Bombay and attended but dropped out of Stanford University’s business school. He now lives in Mumbai with Nita and their three children.

2.       Sameer Gehlaut (40) is the youngest among the 100 richest Indians, ranking No. 97 for a net worth of $1 billion. The former executive at American oil services company Halliburton set up a real estate, financial services and energy empire with two college friends from Delhi’s Indian Institute of Technology in 1999. (The company received financial backing from Indian steel tycoon Lakshmi Mittal soon thereafter in 2000.) Gehlaut has been the chairman of Indiabulls Group since, now three units valued together at $3.17 billion. He is married with two children and lives in Bombay.

3.       Founder of India’s most valuable drug company Sun Pharmaceutical Industries, Dilip Shanghvi (58), ranked No. 2 with a net worth of $18 billion. After graduating from the University of Calcutta, Shanghvi went on to found Sun Pharmaceuticals in 1983 with just five products and a marketing team of two. Shanghvi’s wealth surged 50 percent this year from growth in Sun’s stock after it acquired a rival laboratory from Japan in April. The deal awaits approval from the Indian government, which is determining whether Sun has a monopoly on some drugs. Sun has also had some setbacks this year with two subsidiaries recalling some drugs and the U.S. Food & Drug Administration issuing an alert for drugs imported from one of Sun’s factories. Shanghvi is married with two children and lives in Mumbai.

4.       Diamond jeweler Nirav Modi (41) ranks No. 63 with a net worth of $1.5 billion and counts many on the list as his clients. He drew attention at Sotheby’s auction in Hong Kong this year with an 88-carat diamond necklace that sold for $8 million. He dropped out of Wharton, the University of Pennsylvania’s prestigious business school, and is now expanding Indian sales of his jewelry company Firestar International. In June, he opened his first branded retail store in Delhi with a jewelry line priced at $4,000 and up. He is an avid art collector and lives in Mumbai with his wife and has three children.

5.       The man behind half of all the motorcycles sold in India, and the oldest on the list, is Brijmohan Lall Munjal (91). He ranks No. 23 with a net worth of $3.7 billion, made from his company Hero MotoCorp, a rival to Honda Motor. Hero, worth $4.2 billion, aims to double its sales to 12 million bikes by 2020 and has started building factories in Colombia and Bangladesh. Munjal was born into a middle-class family in 1923 in Kamalia, what was then British India and now part of Pakistan. At age 20, he started a business with his three brothers to supply bicycle parts to manufacturers. They slowly expanded their distribution and by the 1950s were supplying parts across the country. Munjal lives with his wife in New Delhi and has four children.

6.       Savitri Jindal (64), the wealthiest woman in India, made her fortune with her family’s steel business, which she married into and now chairs without being an executive. She has led many community outreach programs through the business. O.P. Jindal Group has rebounded after a three-year decline, due primarily to moves by Savitri’s son, Sajjan, who managed to raise prices for his steel shares, bid for bankrupt Italian steelmaker Lucchini and is reportedly vying with India steel tycoon Lakshmi Mittal (ranked No. 5) to buy Italy’s largest steel plant. Savitri is also a minister in her home state of Haryana, has nine children and has been widowed since 2005, when her husband died in a helicopter crash. She lives in Hisar, where O.P. Jindal was founded in 1969.