The stock market is a marketplace where buyers and sellers trade stocks, which represent ownership in publicly traded companies. There are two main types of stocks - common stocks, which provide voting rights and potential dividends, and preferred stocks, which have a fixed dividend payment and priority in receiving company assets. Investing in the stock market involves buying and holding stocks for long-term growth or trading stocks for short-term gains. To maximize returns, disciplined investing through diversification, rebalancing, and avoiding emotional decisions is important.