People trust friends, family, and people they talk to more than they trust billboards. This makes word-of-mouth very persuasive Word-of-mouth advertising has other advantages, too. It's cost-effective (after all, it's free), and a company doesn't have to create a complex business plan to do it. Many people also use the Internet to review and share products. This is similar to word-of-mouth because people discuss opinions and personal experiences, but many more people can be part of the conversation. You have to be careful about online reviews, though. Unlike a suggestion from a friend or family member, you don't always know who is posting a review online!