A chief operating officer (COO) is another c-level member of companies’ boards. As the name suggests, a COO is responsible for keeping an eye on all corporate operations.
Reporting to the CEO, the COO is also responsible for planning and reformulating operations strategy and policies within the company. If a new approach needs considering, that will have to go through the board for approval.
COOs are usually seen as the next one in the succession line to a CEO, however, there is no obligation to make a COO a CEO if the current CEO leaves the company.