The Bible is not the only means by which God speaks to us but it is the primary way. The Bible is "the Word of God" and is supremely important for the Christian who wants to learn and grow.
It is so important that we have a companion site dedicated to the Bible. There you will find information about the Bible and the type of book it is, as well as about how to read it, study it, etc.. There is also a lot of material introducing you to the various books of the Bible.