How does the stock market works?

It's like asking how does the universe work.....it's not that complicated and not that simple. Your young and unless you have a ton of disposable cash you should not "play" the stockmarket (if that's what your thinking).
First - you should be saving for the future. You should have some cash, then open a retirement account (if you work - if they have one, etc). Once you have "a plan" for the future, and maybe have some money outside of that - then and only then should you consider buying stocks.
Knowledge is power - you should learn the basics - what are stocks, where do they trade, how can I buy them, fees, etc. Find companies you like and follow them. Set up a quote screen, watch them....you can "pretend" or ghost trade for free on some sites...if your in school take a class! Whatever you do - don't listen to some guy saying "hey - I made a million dollars day trading and you can too"....and START SAVING FOR YOUR FUTURE"...OK?....

It is like gambling. The more well educated you are about the companies in which you want to invest, the better off you will be if you want to learn how to buy stocks.

There's a free book about it, which I was thinking about getting for my son, called Unstoppable Prosperity, which claims to be able to keep you surviving even in a down market. (You have to pay for shipping).

No one should try to play the market if they don't know what they are doing.

Magic

Rich people take your money and make themselves more money.

If you just wanna know how to earn from it, well there are two ways fundamental and technical analysis. I personally use technical analysis for my trades and i do intraday.

It tracks the value of individual stock option and business and investors trade them around trying to make the most money by buying low and selling high and making a profit in trade

Trump controls it with his mind

It's a casino for rich people.