Mergers and acquisitions: These two words represent how companies buy, sell and recombine businesses. They're also the reason why today's corporate landscape is a maze of conglomerations. Insurance companies own breakfast cereal makers, shopping mall outlets are part of military manufacturing groups, and movie studios own airlines, all because of mergers and acquisitions.

These businessmen certainly look hostile.

Not all M&As are peaceful, however. Sometimes, a company can take over another one against its will -- a hostile takeover. How can they do that? In this article, we'll find out how hostile takeovers happen, how to prevent them and why a hostile takeover isn't always a bad thing.