What is "Apologetics"?
Apologetics is the art and discipline of giving good
reasons to believe that what you are claiming to be true-is actually true! The apologists tools are many: Philosophy, history, logic, and reasoning.
Apologists use those tools to explain their world view to others, and to convince others to examine their own world view in light of the apologists "apology".
The "apology" then is the argument or evidence built from those tools. This use of the term "apology" may be new to you, as we all know the word as in its usual form to express remorse or sorrow over some wrong or fault committed.

"The Lord's bond-servant must not be quarrelsome, but be kind to all, able to teach, patient when wronged, with gentleness correcting those who are in opposition, if perhaps God may grant them repentance leading to the knowledge of the truth,"
2 Timothy 2:24-25 (NASB)
What is a Christian?
The cross is more than an ancient symbol of an ancient religion.
The cross is the chosen instrument of God's grace and wrath, by which sin (that which severs the God-human relationship) is dealt with once for all time. A Christian is a recipient of that grace, who will also escape that wrath. A Christian has been reconciled to God - the realtionship has been restored, just as God promised through the Hebrew prophets, Jesus, and his chosen apostles.
The Christian Worldview
Don't look now, but your worldview is showing! We all have one. It is that set of specific ideas, facts, and opinions that we believe is "reality." It includes your belief about God, the physical world, morality, ethics and values. It is that which undergirds and informs your actions, decisions and attitudes.
Christians view the world, indeed all of creation, as the product of the one God's free creative choice. All space, time and matter has as its origin that one God. God is the supreme authority in all matters pertaining to faith and conduct, and is therefore the sole basis for morality. Indeed, it is ultimately irrational to speak of morality without God.
Human beings are sinners; that is, relationship with God has been broken and the results are daily seen. As result of this first broken relationship, human relationships are also disordered. Mankind is ultimately and by nature, idolatrous and self seeking, insisting on his or her own code of behavior and thought. The situation is desperate, humans are in need of rescue.
Jesus Christ, in His life, death, burial and physical resurrection, is that rescue. As a substitute standing in the place of sinners, He bore the wrath of God and revealed grace and truth. Redemption is by faith, or trust, that God is pleased to reconcile lost people to Himself through Jesus. That trust is evidenced by a life intent on following Jesus in deliberate actions and thoughts consistent with the truth about God and His will revelaed in the Holy Scriptures - the Old Testament and New Testament.
Learn more about essential Christian doctrine and teaching, flavored with denominational distinctives by reviewing these great confessions and creeds:
Nicene Creed; Westminster Confession of Faith; Baptist Confession of Faith