In my media-ecological research, I have been fascinated by the development and implementation of the ‘tetrad’ by Marshall and Eric McLuhan. First explained in their 1988 book Laws of Media: The New Science, the laws ‘…are intended to provide a ready means of identifying the properties of and actions exerted upon ourselves by our technologies and media and artefacts. They do not rest on any concept or theory, but are empirical, and form a practical means of perceiving the action and effects of ordinary human tools and services’ (McLuhan and McLuhan, 1988, p. 98). To be clear, these laws state that all media/technologies/artefacts must perform the following: enhancement, obsolescence, retrieval and reversal. Each category illuminates not only the functions of any given medium but also its effects on human ability and behaviour.

After watching the live stream of Apple’s first-ever totally virtual, pre-recorded WWDC keynote, I was impressed by the result but also felt the major shift from earlier live streams, which showed people actually presenting physically onstage. Inspired by Andrew McLuhan’s regular sharing of his own tetrads on Twitter, I thought that I would attempt to formulate my own tetrad (above) for this major online event.

The information (message) that was presented by Craig Federighi and co. seemed to be largely the same as that of previous years, however the delivery channel and style (medium) were very different. Taking this noticeable shift and its effects into account, it is important to remember that the medium is the message.

• Source: McLuhan, M. and McLuhan, E., 1988, Laws of Media: The New Science, University of Toronto Press.