What is buying a stock on margin? What may happen if the value of the stock bought

Question:

What is buying a stock on margin? What may happen if the value of the stock bought on margin declines? What are the advantages to investors and brokerage firms when are bought on margin?
Stocks
Stocks or shares are generally equity instruments that provide the largest source of raising funds in any public or private listed company's. The instruments are issued on a stock exchange from where a large number of general public who are willing...