A collective bundle of shares is called "stock". When a company wants to raise money, it can issue stocks to investors. A stock represents a small piece of ownership in the company, and each stockholder is entitled to a share of the company's profits and assets. Stocks can be bought and sold on a stock exchange, and the value of a stock can rise or fall depending on factors such as the company's performance, market conditions, and investor sentiment. The term "stock" can also be used to refer to the total number of shares that a company has issued.