There are numerous philosophies of online teaching and communication is a fundamental aspect. Take a look at this Manifesto and take note of which common views about online classes it is trying to counter:
There are many kinds of online classes, but most feature three elements:
Most have “course materials”. These may be readings, lectures, videos.
In online classes with active teachers, this may include student-student communication and collaboration. In automated classes, interactivity may mean tutorials, quizzes or movies where the user can interact and get feedback.
As the Manifesto notes, assessment need to be traditional. Many different elements can be used for assessing student performance.
And almost all of them have some form of guiding document to tell students what’s going on, whether that be a web page, an email, or a syllabus.