A stock market or equity market is the aggregation of buyers and sellers of stocks (shares). The stock market lets investors participate in the financial achievements of the companies whose share they hold.
A dividend is a payment made by a corporation to its shareholders, usually as a distribution of profits. When a corporation earns a profit or surplus, it can either re-invest it in the business or it can distribute it to the shareholders.
A blue chip is stock in a corporation with a national reputation for quality, reliability, and the ability to operate profitable in good times and bad.
Investing in the stock market does involve a lot of risk. In periods of economic and stock market uncertainty, volatile markets are common and are extremely unsafe. Volatile markets make it difficult to plan with any confidence.