HOW DOES THE STOCK MARKET WORK I'M CONFUSED HELP?

[Cool person]

OK, I got into researching the Stock Market a few days ago and the more I got into it, the more complicated it started seeing. Now, what I know is just that you have to buy and sell stocks at certain times and you either lose or gain money based on your timing. Now, I'm still confused on a couple things.

1. How do the stock prices change??? My best guess is that it is because of the demand of the stock HOWEVER what does it have to do with the actual company then? How does the COMPANY ITSELF determine IT'S OWN stock price, if my guess is correct, then the company that the stock is based on has no effect on it whatsoever which renders it useless.

2. What are dividends?

3. What is a bond?

4. Is there a purpose in the stock exchange now that you can buy stocks online or it serves a bigger purpose?