Moodle blogs provide yet another way to enable you to creatively engage your learners in self expression. The term blog comes from what now is an ancient term Web log coined in the late '90s. Moodle blogs — which can be written and read by instructors and students alike — have replaced the Moodle journal, which is still available but is no longer a default application. (If you want to use Moodle journals, you have to ask your administrator to enable the feature. I recommend sticking with blogs, which your learners are likely to think are a lot cooler than old-fashioned journals.)
Don't worry that the Moodle blog will be available to the whole world. Moodle developers are very clever and have installed tools that enable you to choose who views your blog entries. Also of note, each Moodle user can have only one blog.
As with all other projects and activities that you use with your learners, Moodle blogs need to have a clearly defined learning goal, and you must convey that to your class. Here are a few examples of how instructors and teachers have found versatile uses for blogs: