In this article socialmediatoday they give us the "Big 4":
The preceding information is from the article authored by Genevieve Lachance.
Here's a wonderful summary of the blogging importance in this marvelous infographic from VA Simple Services:
The one item that stood out to me was the Repurpose Content section. Simply put, this is reusing your blog content in other formats:
Here is a blogging book selection from Amazon.