The very first slot machine (called 'Liberty Bell') was created by a man called Charles Fay from his workshop in San Francisco in 1887. Slightly smaller than today's average slot machines, Liberty Bell contained 3 reels and 20 symbols and operated pretty much in same way as today's slot machines. Within a relatively short period of time, Fay's creation became so popular and successful that he began to work overtime in his workshop to meet demand for his slot machines. Capitalizing on their success, Fay rented machines to gambling establishments at a 50% commission rate, refusing to sell manufacturing and distribution rights of his slot machines to gambling manufacturers.
In 1907, Herbert Mills, a Chicago manufacturer created 'Operator Bell', a slot machine similar to 'Liberty Bell' in design. Produced and distributed at a greater rate than Fay's 'Liberty Bell', 'Operator Bell' slot machines experienced even greater success and by 1910, slot machines were very common in United States of America. As soon as slot machines had reached a new peak in popularity and became common throughout USA, new laws were introduced and passed to ban slot machines. In spite of this, slot machines continued to be popular throught America during 1920s and 1930s. During late 1940's, Bugsy, a well known gangster, added slot machines to his Flamingo Hilton hotel in Las Vegas where profit from slot machines eventually exceeded that of table games.
The objective of slot machine is to try and spin a winning combination of symbols on payline.
There are basically two types of slots.
A Straight slots jackpot will remain at a set amount of money until it is won, after which it resets and starts over again at that same amount. For example, a straight jackpot may be set at $20,000 and will remain at $20,000 until it is won, no matter how many coins are deposited into slot machine.
On other hand, amount of money that may be won playing progressive slots is determined by amount of money deposited into machine. Thus progressive jackpot continuosly increases with each player until it is won.