Is there a difference between theology and apologetics? I've heard that it all has to do with knowing the right audience. Perhaps, if the audience be Christian, it would be labelled as "theology", and if the audience is non-Christian, it would be labelled as "apologetics". So, apologetics might be just Christian theology re-packaged to a non-Christian audience.

(There is this book by R.C. Sproul, and I suspect that he is writing to a Christian audience by his usage of "we", making it sound like an ordinary textbook or handbook on theology. However, the term "we" can be re-interpreted as "the author and other orthodox Calvinists", making it sound like proselytism. Either way, it is clear that R.C. Sproul is writing with a specific purpose: to persuade the reader his own view of God, the Holy Trinity, or the Holy Spirit. And if the reader buys it, believes it, is changed by his writing, then he'd fulfill his purpose as a writer. Writing is an art. An art of persuasion.)
"Theology" is the study of God, the gods, and related ideas like angels and demons and heaven and hell.

"Apologetics" is the defense of a theological position.

You could say that apologetics is a subset of theology, that part of theology concerned with proving (or at least, arguing) that the rest is true.