Push-buttons are part and parcel of the economic, cultural and political texture of today's big-data capitalism. How did this communication and control interface become so widespread? What lies behind the gesture of pushing a button? This excellent book at the intersection of media studies, history of technology and cultural history deals with the materiality of power. It advances towards a genealogy of the digital present (in the double sense of the importance of fingers and of binary logic) through the history of an interface that reconfigured how humans interacted with each other and with technological systems.

Power Button focuses on the period of the emergence and early adoption of push-buttons in wealthy urban contexts in the United States (1880–1925). The book is solidly grounded in a vast and extremely rich set of textual and visual sources, ranging from patents, commercial catalogues and technical journals to popularization magazines, fiction and advertisements. This variety of sources allows for a historical analysis of the design, production, circulation and (mis)use of push-buttons, as well as their entanglement with the emergence of an ideal of ‘digital command’.

One of the main arguments of the book is that push-buttons became such a successful interface because they materialized a certain ideal of technological delegation that promised instant gratification while black-boxing all the sociotechnical infrastructure and power relations behind them. Manufacturers and advertisers constructed an imaginary of effortless, foolproof, ergonomic, automatic ‘digital command’ that could instantly fulfil anyone's desires with the ‘mere touch’ of a button regardless of strength or technical skill.

In addition to analysing the early cultural history of this ideal, Plotnick's attentive gaze uncovers and describes a complex phenomenology of actual interactions that demonstrates how the push-buttons used to operate an elevator, ring a doorbell, call for a servant, turn on the light, trigger an alarm or take a picture were mechanisms that embodied and shaped power relations, applied and distributed force and organized things and bodies in space.

Plotnick emphasizes the embodied nature of the human–machine interaction. On the one hand, she historicizes ‘hand practices’ and reflects upon the politics of touch in modernity, which is usually analysed in visual terms (Plotnick was one of the contributors to a 2017 special issue of the journal New Media & Society that promoted the new field of ‘haptic media studies’). On the other hand, she stresses the political relevance of the fact that the bodies whose fingers pushed buttons, as well as the bodies that were pushed into action, were situated in terms of class, gender, race and age.

The book is divided in three parts. The first one, ‘You rang?’, deals with push-buttons as technologies to regulate the presence or absence of other people, from servants and employees to policemen and firefighters. Plotnick explores how in the early years of electrification the integration of push-buttons into affluent domestic spaces, offices and hotels was embedded in ideas and practices of service and servitude. The push-buttons that replaced bells to summon servants in wealthy homes were at the same time a way to domesticate electricity and a way to minimize the effort of those who commanded with the finger, while maximizing the power over the subalternized bodies of those who worked with the hands and were kept invisible until needed.

The second part, ‘Automagically’, deals with push-buttons as tools of activation that put machines into action with little human intervention. On the one hand, Plotnick explores the romanticized views of powerful button pushers producing spectacular distant effects, such as the president turning engines on at the inauguration of a World's Fair, or young girls detonating a mine or activating a dam from a distance (symbolizing that the ‘mere touch’ of a button could empower even what were considered the frailest bodies). On the other hand, she analyses fears of the irreversible effects of pushing a button through examples such as push-button warfare and the ethical debates about button-mediated killing with electric chairs. Plotnick also focuses on the imaginaries and practices of technological delegation in labour and consumption. The reconfiguration of technology users as passive pushers of black-boxed mechanisms in search of instantaneous gratification is analysed through the debates about de-skillment and unemployment spurred by the commercialization of automatic cameras, elevators and vending machines.

The third part, ‘Imagining digital command’, deals with the cultural perception of push-buttons. Plotnick explores the debates about what should be their functions, the conflicts and negotiations between their prescribed and actual uses, and their entanglement with redefinitions of pleasure and consumption. At a time in which push-buttons were not yet widely used, Plotnick argues that they functioned as ‘dream machines’ that promised a pleasurable (or nightmarish) future in which any desire would be satisfied through an effortless pushing experience.

Finally, the conclusion deals with the rest of the twentieth century and argues that the ideal of ‘digital command’ persists to this day. While the continuities stressed by the author are convincing, further research on the discontinuities introduced by electronics, cybernetics and computing would be welcome in order to link the early history of push-buttons with the current buttonization and monetarization of social relations through gamified confessional platforms (Ippolita, Anime elettriche: Riti e miti sociali (2016)). Also, further research about other areas, such as ‘interactive’ museums and the educational uses of push-buttons, might enrich the analysis, and the inclusion of other geographical contexts would make it global.

Power Button is an important book that makes substantial contributions to the histories of electrification, domestic labour and automation in the United States by stressing the relevance of interfaces as well as the imaginaries and embodied practices of ‘digital command’. It is also, and most importantly, a major contribution to the historical understanding of the politics of human–machine interaction.