Public companies has shares which can be traded publicly on a stock market. Private company becomes a public company when it offers the shares of the company to public. Public companies are run by a board of directors. This is because the firm will be compelled to increase shareholder value. Shares that increase in value are more desirable for investors, who are then less likely to sell the shares. Private companies have a group of investors.They usually have few shareholders. The business decisions here are made by either the business owners or investors rather than managers. Private companies mainly rely on proft and they will not share their financial information. Public companies uses stocks to invest in their new project for the company growth. Stryker, Molecular Imaging are examples for public company. Ikea is an example for private company.