The stock market is a network of exchanges where shares of publicly traded companies are bought and sold, providing investment opportunities and enabling price discovery based on supply and demand. Major exchanges like the Bombay Stock Exchange and National Stock Exchange play crucial roles in facilitating trade and maintaining market integrity, while regulations from SEBI protect investors and promote fair practices. Factors such as economic conditions, company performance, and investor sentiment influence stock prices and investing strategies including long-term investing and diversification can help manage risks.