This document discusses mergers and acquisitions. It defines a merger as occurring when two or more existing firms combine to form a new entity, usually through friendly negotiations. An acquisition refers to one company purchasing a controlling interest in another existing company, allowing two companies to remain separate legal entities but resulting in a change of control. Several examples of large mergers and acquisitions are provided, such as the 2010 merger of United and Continental Airlines and acquisitions by 5 MG PLC and other companies worth billions of dollars.