Matka (also known as Satta) is a form of gambling that was created in Mumbai, India. The game really took off in the 1970’s until the 1990’s under the influence of Ratan Khatri. Mr. Khatri is known as the "Matka King" and is credited with transforming Matka into the largest gambling craze in the whole of India.

Matka is a game in which people bet a stake on random numbers drawn. The original form of the game was played by betting on the opening and closing rates of wholesale cotton traded on the Bombay Cotton Exchange at Siwri. For many years this was the only way of betting on figures.

Ratan Khatri devised a system of betting on figures made up from the total face value of three cards drawn twice a day. If the first draw made, for example, was Ace, seven, eight (Ace has a value of 1) then the total face value would be 16. This value would need to be changed into a single digit so the opening number for the first draw would be 7. There would be a “matka” or pot shown on various places throughout the city that looked like this: 178 7x

The second draw was usually made at midnight and if the cards drawn were 5, 3 and 6 then the “matka” displayed would be shown as 178 7×5 536.

Players can bet on the numbers they think will be the opening and closing values and if they get both right they win 80 times their stake. If the player bets only on the open or close numbers and guess the correct number they will win eight times the stake.

If somebody bet Rs1 on the number 75 being the "open/close" number in the previous example they would win Rs 80. Usually players try to make multiple bets so as to try and guarantee as much as possible some sort of return on their stake.

Matka payouts are usually made the day after the draw and five "satta" sessions are conducted each week. It is estimated that the Matka industry is worth around Rs 350 crore (Rs 3,500,000,000) each year.