What Exactly Is the Holy Spirit?

Is the Holy Spirit an independent Personality or Person, or does it at least exist in some way as a conscious entity which is separate from the Father and the Son? If not, how are we to understand biblical Scriptures which seem to indicate that the Holy Spirit speaks or acts; and that this happens independently of God the Father and Jesus Christ? Upon closer examination, we will see that those passages, as well as the entire teachings of the Bible, convey something completely different from what is commonly assumed.