What is the best way to describe a stock market?

The stock market is a financial institution where there are individuals (stock brokers) and firms (brokerage or investment firms) which engage in the trade or buying and selling of company stocks. Stocks are financial instruments which company's sell granting partial ownership and certain rights to dividends of a company's future earnings. The stock market is a speculative market whereby individuals or firms buy and sell stocks as the the profitability of companies goes up and down in real terms and also in projected or expected terms.