The stock market is a share market, where shares are bought and sold however besides shares of companies, other instruments like bonds, mutual funds and derivative contracts too are traded in the stock market.
The share market is a source for companies to raise funds and for investors to buy part-ownership in growing businesses and grow their wealth. On becoming a shareholder, an investor earns a part of the profits earned by the company by way of dividend. At the same time, the investor also undertakes the risk to bear loses, should the business fail to perform well.