Actually, I’m forgetting a step.
Where did you come from? You might say “my parents”, or if you are a smartass, something like “Pittsburgh”. And where did your parents come from? “Their parents” and so on. If this goes on long enough, eventually “their parents” will NOT be a valid answer. There are two major theories and some minor ones which attempt to answer this.
One set of theories is that there was nothing and then suddenly something (the Big Bang Theory) and then this something eventually followed the laws of physics and became the physical universe. Because this particular planet just happened to be “perfect” for our form of life, life eventually happened and evolved until eventually our immediate precursors happened to exist and generated the first set of parents (the Theory of Evolution).
The other major theory is that there was nothing and then God created everything (Creation Theory). A sub-theory of this is that God “guided” physics and evolution to create the universe and us. Basically, either “we” happened accidentally or as the result of some intelligence (Intelligent Design).
Note that any theory which postulates that we are the result of a non-God intelligence is not useful, since it just moves the question back a level. “We were seeded here by aliens”. “Really, well then, where did the aliens come from”? And so on. Oh, and don’t ask me where God came from, since most concepts of God requires that He has always existed (a difficult to grasp theoretical aspect of the Supernatural world).
If you believe that no God exists, then you are stuck with the Theory of Evolution, which is not contradicted by currently known facts, but is also not proven by them. However, if there is the possibility that God does exist, then He could have made the original set of parents, and maybe even exerted some amount of control over your existence.
In the next part, we will consider the possibility that you have a Supernatural aspect. Really.