Company, legal entity formed for the purpose of conducting business that is separate from its owners, the shareholders. A company continues to exist despite changes in (or deaths among) its owners. A company can hold assets; it can sue, and it can be sued. Various documents have to be filed when forming a company. In the United Kingdom these include the Memorandum of Association and the Articles of Association, which together spell out the objects of the company (in broad terms, what kind of business it will be engaged in) and the internal regulations governing the conduct of company business. In the United States, the equivalent documents are the Certificate of Incorporation and the Bylaws. Companies are also governed by company law, as laid down by legislative acts over the years. Such laws spell out, among other things, auditing and accounting requirements, the duties of company directors, and the rights of shareholders.

Most companies have limited liability; in other words, owners are liable for a company's debts only up to the value of their shareholdings. Categories of companies vary from country to country and go by different names. The main difference is between public and private companies. Public companies can sell their shares to the general public (which they usually do through a stock exchange); private companies cannot sell shares to or raise money from the general public. In general, private companies tend to be smaller than public companies. However, some of Germany's biggest companies are privately owned.

Some of the names by which public companies are known include: Public Limited Company (plc) in the United Kingdom; Société Anonyme (SA) in France; Aktiengesellschaft (AG) in Germany; Società per azioni (SpA) in Italy; Sociedad anónima (SA) in Spain.

Some of the names by which private companies are known include: Private Limited Company (Ltd) in the United Kingdom; Société a responsabilité limitée (Sarl) in France; Gesellschaft mit beschrankter Haftung (GmbH) in Germany; Società a responsabilità limitata (Srl) in Italy; and Sociedad de responsabilidad limitada (Srl) in Spain.

Within the public/private division, other types of company include: (1) associated company, which in the United Kingdom is a company over which another company has substantial influence; for example it owns between 20 per cent and 50 per cent of its shares; (2) holding company, a company that owns another company or other companies and which is sometimes referred to as the parent company (most public companies operate through a number of companies controlled by the group's holding company); (3) subsidiary company, a company controlled by a holding company, usually because the holding company owns (or indirectly owns through another subsidiary) more than 50 per cent of the subsidary company's shares.