The most common form of interaction in an online course is through the discussion board using forums established by an instructor with students responding with threads. If given the option, students can subscribe to forums or threads, attach files, embed videos and images, rate and quote classmates' threads.
Journals are a personal space for students to communicate privately with the instructor. Students can also use journals as a self-reflective tool to post their opinions, ideas, and concerns about the course, or discuss and analyze course related materials.
A blog is a personal online journal that is frequently updated and intended for general public access and use. Blogs also have a commenting system, so that students can respond to and interact with one another. Instructors create and manage blogs, and only enrolled users can view and create entries and comments in them.