You are reading this in your browser. I don’t know what kind of device you are using, or which operating system, or which browser in particular (Chrome, Safari, Firefox etc.). But I can describe, with some confidence, a series of nested frames around these words: the TextWork title bar; the browser window, with its own title bar, tabs etc.; perhaps the edges of other programme windows or a desktop ‘behind’ the browser; the operating system menu bar, and perhaps a dock of applications; the rim of the device itself, a perimeter of metal, plastic or glass; and then, framing that, ...