The Blog Content
Content is the raison d'être (http://www.bartleby.com/59/4/raisondetre.html) for any web site. Retail sites feature a catalog of products. University sites contain information about their campuses, curriculum, and faculty. News sites show the latest news stories. For a personal blog, you might have a bunch of observations, or reviews. Without some sort of updated content, there is little reason to visit a web site more than once.

On a blog, the content consists of articles (also sometimes called "posts" or "entries") that the author(s) writes. Yes, some blogs have multiple authors, each writing his/her own articles. Typically, blog authors compose their articles in a web-based interface, built into the blogging system itself. Some blogging systems also support the ability to use stand-alone "weblog client" software, which allows authors to write articles offline and upload them at a later time.