I am 17, is it possible for me to invest in stock market? if yes then how?

[Donut Tim]

Yes, it is possible.
If you are under age then you can have a parent or guardian open a custodial account for you.

You and your guardian should go to a brokerage such as Scottrade or TD Ameritrade. They will have papers to fill out and sign.

Afterward, you can trade online.
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If you buy stock hoping that you can sell it for a quick profit because of the daily (or monthly) swings in price, then you are not investing. You are hoping that for some unknown reason, the trading price will go up instead of down, and that you can outguess the public and sell at the best price. That is gambling.
Instead of gambling, choose a company that has steady earnings each year instead of losses. If your company has very little long term debt, it will likely not get into financial trouble. Don't pay more for the shares of stock than they are worth. If you pay 25 times earnings for a stock, you are only getting a 4% return. If earnings are steady, you will need 25 years to earn your money back on this stock. That's horrible.
Ignore the short term swings in the stock prices.

Buy these sturdy stocks and hold on to them. When you hold these stocks over a period of time, the prices will go up for a real reason; the companies are earning money every year and becoming more valuable.

If you save a portion of your income each payday and invest in solid stocks, over the course of several years you can grow very wealthy indeed. It is like hiring someone to go to work and earn money for you, and then using that money to hire more workers. Your money grows geometrically.

Some people can learn from the mistakes of other people. Gamblers can't and usually ignore advice like this.
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