A company is defined as an artificial legal entity created under the Companies Act. It has key characteristics such as being a separate legal entity, having perpetual existence, limited liability for members, and separation of ownership and management. The document discusses the different types of companies in India according to the Companies Act - One Person Company (OPC), Private Limited Company, and Section 8 company for non-profit activities. Private Limited companies have a maximum of 200 members and 2-15 directors, while OPCs can only have one member but up to 15 directors. Section 8 companies are for charitable goals and cannot pay dividends.