What are interfaces for, really?

In computing, context is everything. The same pattern of zeroes and ones (binary digits) represents a number in one context, a letter of the alphabet in another context, and an instruction to the processor in another. The computer instructions that create the on-screen “furniture”’ of our human-computer interfaces are, at the lowest level, no different from the texts to which they seem to give shape, enabling our interactions. The best interfaces make apparent this ontological sameness while the worst reify abstract high-level distinctions between form and content, enforcing power relations between the makers of digital content and their consumers.