Popularization in this article specifically refers to “a vast class of various types of communicative events or genres that involve the transformation of specialised knowledge into ‘everyday’ or ‘lay knowledge’” (Calsamiglia & Van Dijk 2004: 370), so is not to be confused with the meaning which is usually associated with the adjective popular, i.e. to be liked, or enjoyed by a large number of people. Lay public is different from science experts in that they are more concerned about the application, the utility and the consequences of science findings in relation to their daily life, rather than the advancement of science theories or methods (Calsamiglia 2003: 139). The expert-lay communication has attracted much interest from researchers in a range of disciplines, including linguistic studies, media studies, and science communication (Myers 2003: 265). Popularization can take place in different modes, not only in the written form, but also through audio-visual channels, internet, and other sites such as science museums. Therefore, popularization research often involves multimodal analysis (e.g. Macdonald 1996; Santamaria, Bassols & Torrent 2011). In fact, the emergence of new media is a main reason of the wide dissemination of science knowledge to the public.