What are prices?

Answer 1

When a business needs to raise cash, they arrange to sell shares of the business to individual people. There are regulations to be followed, but basically a share is a piece of ownership of the company. If you buy a share, you own that much of the company. The share price is what you have to pay for it.

If a lot of people want the shares, and there aren't enough to go around, the price will go up. If people don't trust the company, they all try to sell their shares and the price of each share will go down.