Alessandro massa mesmo esse topico. Aprendi mais uma hoje. Aqui mais informacoes sobre o termo:
Word of mouth is a reference to the passing of information from person to person. Originally the term referred specifically to oral communication[1] (literally words from the mouth), but now includes any type of human communication, such as face-to-face, telephone, email, and text messaging.
History of word of mouth marketing
One of the earliest Australasian references to and the active use of the term 'Word of Mouth Marketing' was by an Australian MLM company from the mid 1980's. This company may possibly have been the originator of the term. This company promoted its alternative-to-dairy product range through this method, especially to those with asthma, dairy allergies and cardiac issues. The related topics became a conversational piece, so product promotion and trial naturally resulted
Word of mouth marketing
Word-of-mouth marketing, which encompasses a variety of subcategories, including buzz, blog, viral, grassroots, cause influencers and social media marketing, as well as ambassador programs, work with consumer-generated media and more, can be highly valued by product marketers. Because of the personal nature of the communications between individuals, it is believed that product information communicated in this way has an added layer of credibility. Research points to individuals being more inclined to believe WOMM than more formal forms of promotion methods; the receiver of word-of-mouth referrals tends to believe that the communicator is speaking honestly and is unlikely to have an ulterior motive (i.e. they are not receiving an incentive for their referrals).[2]
To promote and manage word-of-mouth communications, marketers use publicity techniques as well as viral marketing methods to achieve desired behavioral response. Influencer marketing is increasingly used to seed WOMM by targeting key individuals that have authority and a high number of personal connections.
Marketers place significant value on positive word-of-mouth, which is traditionally achieved by creating products, services and customer experiences that generate conversation-worthy "buzz" naturally[3]. The relatively new practice of word of mouth marketing attempts to inject positive "buzz" into conversations directly.
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http://en.wikipedia.org/wiki/Word_of_mouth