Stocks are a part ownership of a company. However, this definition is dangerously reductive. A stock is issued by the company, and the company remains at all time a separate entity from the shareholder.

 The owner of the stock is not liable to pay the debt of the company in case it goes bankrupt, and a company doesn’t have to share its profits with the stock owner – just look at most large technology companies, the pay no dividends! Since stocks are normally issued by large corporate bodies where ownership is spread across many power groups and individuals, there is a so called Separation of Ownership and Control. 

Most big companies have a CEO, who is entrusted, usually through a vote among the shareholders, with the task of running the company. Outside of the right to vote, a stock owner has only the power to sell his own shares or buy someone else’s to increase his position.