This chapter considers the various types of modern company. Modern companies are used for many more purposes than were ever considered by the people who drafted the early companies legislation. Just as Aron Salomon hit upon an imaginative use of the limited liability company (as considered in the previous chapter), so there have been many more uses developed by clever practitioners to help their clients since then. Aron Salomon used the company to avoid the possibility of personal liability for the potential failure of his business. However, as we shall see, most companies in existence today have no trade at all because they are used either simply to hold assets or as holding companies in trading groups. Most company law scholarship is concerned with trading companies, although there are many differences between individual trading companies. We shall consider the different ways in which various types of people may think about the same trading company: whether as creditors, employees, directors, customers, policymakers, or long-term or short-term shareholders. We shall also consider how different types of company have different impacts on the economy. Finally, we shall also consider the various ways in which modern company law theory has explained the nature of the company. Our consideration of company law in this book will be greatly assisted by understanding how companies are used in the real world and how they affect ordinary people.