My First Blog!!

So, what does one do on a blog?  Do I write about things that people may or may not care about and hope that someone reads it and gets some good out of it?  Do I ask questions that stir up questions and generate debate and discussion?  Do I vent my frustrations to the world wide web and not care if anyone reads it as long as I get to say it?  Do I share some insights that I have gotten from my study of the Bible?  Could I share prayers for things and people