口耳相传，又称口口相传，是通过个人与个人之间的推荐，提供消息来进行信息传递的一种方式。与广告，大众媒体相左。

口碑行销（Word of mouth marketing (WOMM)）乃是一种透过口耳相传方式来进行的行销方式。如直销（Direct Marketing）是一种口碑行销方式。另外，随着传播技术和现代网络的发展，网络口碑（electronic word of mouth)的概念被提出，冲击并完善了传统口碑的概念。

Marketing buzz or simply buzz—a term used in viral marketing—is the interaction of consumers and users of a product or service which amplifies or alters the original marketing message. This emotion, energy, excitement, or anticipation about a product or service can be positive or negative. Buzz can be generated by intentional marketing activities by the brand owner or it can be the result of an independent event that enters public awareness through social or traditional media. Marketing buzz originally referred to oral communication but in the age of Web 2.0, social media such as Facebook and Twitter are now the dominant communication channels for marketing buzz.