Cornelius Van Til states that "Apologetics is the vindication of the Christian philosophy of life against the various forms of the non-Christian philosophy of life." In other words, the entire Christian worldview is brought into conflict with all other forms of non-Christian thought. I have found it helpful to "cut the pie" of apologetics into the following seven sections with some sample particulars. There are other ways to conceive of this but the following helps to show all the different kinds of things defending the faith deals with.
1. Philosophical Issues
* Proofs for God's existence * Problem of evil * Relation of faith and reason * Coherence of the nature of God2. Scientific Issues
* Creation and evolution3. Historical Issues
* Historicity of resurrection * Reliability of text of OT and NT * Biblical archaeology4. Biblical Issues
* Alleged Bible contradictions * Biblical portrait of God--is he good? * What about various actions or laws in the Bible--do these make sense (example: slavery).5. Theological Issues
* Are the Christian doctrines rational or do they violate logic? -Trinity -Incarnation -Atonement -Humanity having a "soul"6. Cultural Issues
* Abortion * Gender & Sexuality issues * Suicide & euthanasia7. Other Worldviews and Religions
* Nihilism, Existentialism, etc. * Buddhism, Hinduism, Islam * Cults and Deviations from OrthodoxyOf course, there is overlap between the categories. For example, the issue of the "soul" or mind is a theological issue but it also is a philosophical and scientific issue--at least those categories come into play. So this is not the official list of apologetics! It does, however, begin to show how extensive the task of defending the faith is in our contemporary context. The Christian faith deals with all of life and the opposition to Christian theism will be across the full spectrum of life. No one person is an expert in every arena listed above. We need all sorts of individuals involved. Even if you do not feel called to this task yourself you can pray for Christian scholars who do engage in these areas. Ask God to raise up those to defend his Word and ways!