What is the difference between a closely held corporation and a public corporation?

A closely held corporation is one whose shares are owned by a few shareholders who are often family members, relatives, or friends. These "close" shareholders are often involved in the direct management of the corporation and sometimes enter into buy-and-sell agreements that prevent outsiders becoming shareholders. Conversely, publicly held corporations often have many shareholders, for which shares are traded on organized securities markets. These shareholders rarely participate in management activities.