In the last decades of the 19th century education played a major role in Mexican society, when efforts were being made to restructure it based on the objective teaching of sciences, which was regarded as the driving force behind the change needed in various sectors such as industry and public health. In this context, the so-called science disseminators aimed to communicate their knowledge to the general public, mainly to the working classes and the children. Journalism grew and reached a wide range of themes and audiences. They believed in the idea of a science for all and that sciences were an instrument to know the new nations and educate the population. It is worth mentioning La ciencia recreativa, a publication dedicated to children and working classes. Between 1871 and 1879 it was edited by the topographical engineer and surveyor José Joaquín Arriaga (1831–1896), who aimed to generalise the scientific knowledge of cosmography, mineralogy, meteorology, physics, botany, zoology, descriptive geography and industrial agriculture.

As a case study, we analyze an article of the psychiatrist Henrique Roxo published in 1942 in two publications directed to different publics. The communication of science was intended as part of Brazil's modernizing project of the epoch. Roxo's case reveals that the language used by science communicators, although sometimes of difficult apprehension, was part of an strategy of acknowledgment of the medical authority for the diagnosis and treatment of the mental illnesses.

Science communication is today a well-established ―although young― area of research. However, there are only a few books and papers analyzing how science communication has developed historically. Aiming to, in some way, contribute to filling this gap, JCOM organized this special issue on the History of Public Communication of Science and Technology (PCST), joining 15 contributions, from different parts of the globe. The papers published in this issue are organized in three groups, though with diffuse boundaries: geography, media, and discipline. The first group contains works that deal descriptively and critically with the development of PCST actions and either general or specific public policies for this area in specific countries. A second set of papers examines aspects of building science communication on TV or in print media. The third group of papers presents and discusses important PCST cases in specific areas of science or technology at various historical moments.

By focusing on a specific episode of 20th Century physics — the discovery of parity violation in 1957 — the paper presents a study of the types of explanations of the crucial experiment as they are found in different editorial categories: a peer-review journal, a popular science book, an encyclopedia and a newspaper articles. The study provides a fine-grained description of the mechanism of the explanation as elaborated in non-specialist accounts of the experiment and identifies original, key-explanatory elements which characterize them. In so doing, the paper presents a reflection on the processes of transformation and adaptation implied by the circulation of knowledge — which features as a productive process in its own right — and shows which further insights a focus on explanation can offer to the current historical researches on science communication.

During the course of several decades, several scientists and groups of scientists lobbied the British Broadcasting Corporation (BBC) about science broadcasting. A consistent theme of the interventions was that science broadcasting should be given exceptional treatment both in its content, which was to have a strongly didactic element, and in its managerial arrangements within the BBC. This privileging of science would have amounted to ‘scientific exceptionalism’. The article looks at the nature of this exceptionalism and broadcasters' responses to it.

This paper explores the combined effects of everyday life technological devices and advertisements in constituting an efficient way to scientific popularization. We, therefore, analyze mobile telephony advertisements published in a high-circulation Spanish newspaper — La Vanguardia — between 1994 and 1999. We identify content that promoted knowledge about the devices, the service, or the uses of this groundbreaking technology. Advertisements also attach attributes to technology — modernity, freedom, or efficiency. We suggest that the analysis of advertisements that promote everyday life digital devices allows a better understanding of what (digital) technology means to publics.

Social media is restructuring the dynamics of science communication processes inside and outside the scientific world. As concerns science communication addressed to the general public, we are witnessing the advent of communication practices that are more similar to public relations than to the traditional processes of the Public Understanding of Science. By analysing the digital communication strategies implemented for the anti-vaccination documentary Vaxxed, the paper illustrates these new communication dynamics, that are both social and computational.

Online visual communication of science focuses on interactive sharing and participatory collaboration rather than simple knowledge dissemination. Visuals need to be stunning to draw people in and engage them, and a cross-media approach together with digital multimedia tools can be used to develop a clear and engaging narrative to communicate complex scientific topics. On the web both science communicators and the public manage co-create, shape, modify, decontextualise and share visuals. When it happens that low science literacy publics devoid a picture of its information assets, caption or source, they distort image meaning and perpetuate misinformation.

The future challenges within science communication lie in a 'grey area' where the frontiers between production and sharing of knowledge are blurred. An area in which we can satisfy at the same time and within the same activity the autonomous interests of researchers and those of other stakeholders, including lay publics. Settings are emerging, where we can provide real contribution to scientific research and at the same time facilitate the publics in their process of hacking scientific knowledge to serve autonomously defined and often unpredictable functions. Some are linked to research institutes, others to science centres, others are precisely inbetween. This editorial explores why these special places are needed, and present some case studies, leading to the need of interpreting science culture centres as research facilities.

Although with some reluctance, social sciences now seem to have accepted the challenge deriving from the growing digitisation of communication and the consequent flow of data on the web. There are actually various empirical studies that use the digital traces left by the myriads of interactions that occur through social media and e-commerce platforms, and this trend also concerns the research in the PCST field. However, the opportunity offered by the digitisation of traditional mass media communication — the newspapers in particular — is much less exploited. Building on the experience of the TIPS project, this paper discusses the advantages and the limits of computational social science on PCST using newspapers as the main source of data. Some methodological issues are also addressed, in order to suggest a more aware use of such data and the several computational tools available for analysing them.