Online or electronic word-of-mouth (eWOM) has been defined as “any positive or negative statement made by potential, actual, or former customers about a product or company, which is made available to a multitude of people and institutions via the Internet” (Hennig-Thurau, Gwinner, Walsh & Gremler, 2004, p. 39). Moreover, eWOM also includes opinions and share of information not only about products but also about services and brands (Jalilvand, Esfahani, & Samiei, 2011). In this post I will address the question: what are key characteristics of eWOM that companies need to know in order to manage it effectively?