This is a kind of inside-baseball question, I think. For the typical English speaker, theory means something like speculation. In more academic/research contexts, theories are the conceptual basis for the work we do: e.g., a theory of evolution. The OED provides this helpful definition that is closer to what I had in mind as a starting point:
An approach to the study of literature, the arts, and culture that incorporates concepts from disciplines such as philosophy, psychoanalysis, and the social sciences; esp. such an approach intended to challenge or provide an alternative to critical methods and interpretations that are established, traditional, and seen as arising from particular metaphysical or ideological assumptions.Oxford English Dictionary
Certainly when I was a grad student in the 90s, and perhaps still today, this is what was meant by Theory, often with some modifier: poststructuralist, feminist, Marxist, postcolonial, psychoanalytic, etc. Such is the way of things though that what once challenged establishment thinking goes on to become the established thinking only then to be challenged anew. One good turn deserves another, or something like that. And perhaps such is just the natural history of ideas. If so, you’d imagine this would have been going on for many generations, but not so much. Theory was an invention of the 1980s, even though it was built upon texts from the 60s and 70s. (The OED helpfully points to a 1982 reference as its earliest marker.)
Surely we can’t go on like this, can we?
For one thing, it’s a little confusing. Basically any even modestly complex task is going to have a conceptual basis, a theory. There’s a theory to baking. There are theories behind every exercise program. There are design theories, musical theories, and art theories that each provide a conceptual basis for a practice. Similarly there are theories of writing and rhetorical practice. But none of these are necessarily Theories, though they could be: a psychoanalytic theory of baking, a poststructural theory of art, a feminist theory of exercise, and so on.
Having moved to Media Study, I find myself thinking particular about media theory. Of course there are media theories of the same variety as there are literary theories (literature being media after all). There are also social scientific media theories, which is a separate subject. If you google “media theory,” then you’ll probably encounter them first. But what of humanistic-philosophical media theories? McLuhan is an example, at least historically. Maybe the Frankfurt school and the culture industry, though perhaps that’s Marxism applied to media. Later, there is German media theory (e.g., Kittler) and media archeology. Without going into great depth, I’d say media archeology is a good example of a theory that is specific to the study of media (and of course, those other theories are laid upon it so that we get feminist media archeology and so on).
Of course there are a whole slew of different kinds of studies: software, platform, critical code, media infrastructure, video game, etc. I think of film/cinema studies and television and pop culture studies as separate, primarily because they have longer, pre-digital histories. Film studies produes film theories that are specific to the study of film. Film studies/theory aside, these other studies, in my view, describe specific objects of study rather than unique theories.
So what am I getting at? I guess I’m trying to figure out what it would mean to teach media theory. On the one hand it could like mean teaching Theory in the context of objects of media study. E.g., I could teach actor-network, assemblage and/or posthuman theories (not talking about teaching some broad intro course here); those are (or could be) media theories. On the other hand, I could teach scholarship in software studies or media infrastructure studies or some such. That would get you more insight into scholarship in the field and the use of various theories, but it wouldn’t really teach the theory directly. Both approaches are useful, and I could probably mix them up some how. Indeed many monographs and articles, including my own, aim to do both, so it’s hard to disentangle the theorization of media from the study of media.
Maybe it’s a moot question or maybe it’s the question that matters rather than the answer. Which is more at stake, the blackbird or the ways of looking? The world or how we see it? The classic idealist response is that there is an uncrossable void between the two. A different answer is that how we see the world is part of the world. Our sensations may be fleeting in material terms, but so are our lives on a cosmic scale. It doesn’t make them less real. From that perspective, theorizing (media or otherwise) adds to the world (rather than unveiling it, hermeneutically). Theory as method is theory as doing, as making.