But the list also contains some of India's leading figures in manufacturing, including Dhirubhai Ambani who heads the $6.6bn Reliance Industries.

India's richest

Azim Premji $6.9bn Dhirubhai Ambani $6.6bn Shiv Nadar $3.7bn Subhash Chandra $3bn Lakshmi Mittal $2.1bn Vinay Rai $2bn 224. K Birla $1.7bn BR Raju $1.3bn Hinduja family $1bn

Azim Premji, founder and chief shareholder in Wipro, India's leading information technology firm, created a stir in February when he was estimated to be the fourth richest man in the world.

But a plunge in stock prices saw his net worth drop from $35bn to $6.9bn and the 38th spot on the Forbes list.

Mr Premji's company is based in the Indian cyber-city of Bangalore and he has a reputation for being thrifty and keeping a low-profile.

Despite his immense wealth, he drives a Ford Escort, flies economy class and queues up with his employees for lunch at the staff canteen.

Humble origins

At 40th place is Dhirubhai Ambani, India's largest petrochemicals manufacturer.

His Reliance Industries has interests in telecommunications, power and infrastructure development and recently announced plans to join the IT boom.

Azim Premji is India's richest person

Mr Ambani's rise to his present position is part of Indian business lore. Born poor, he left his home state of Gujarat for the Gulf to take up a petty job in Aden.

He built up his giant empire from scratch to become one of India's biggest industrialists - a position which led to a one-on-one meeting with Bill Clinton in Bombay, earlier this year.

Two other industrialists who have diversified from their manufacturing past into IT also made it to the list.

The fifth richest Indian, Lakshmi Mittal, owns a steel empire with acquisitions in Indonesia, Uzbekistan, UK and the US.

He has now launched Metique, a global procurement portal for metals

Kumaramangalam Birla, from one of India's leading business houses, inherited a $4bn commodities empire and the country's largest private sector mutual fund company.

He has now acquired Byte International, a US-based e-learning company.

Media and IT kings

The list also contains one of India's hottest media czars, Subhash Chandra, a former rice trader who now owns Zee Telefilms.

Mr Chandra's $3bn fortune comes from a massive media empire which includes television channels, production companies, studios, broadband internet services and amusement parks.

B Ramalingam Raju, who was educated in the US, also figures in the list, with assets worth $1.3bn.

He launched India's very first IT service provider, Satyam Infoway.