A block usually displays information in a small area in one of the side columns. For example, a block can display a calendar, the latest news, or the students enrolled in a course. Think of a block as a small applet or widget.
They can also include links to parts of the course and thus be something like navigation bars. Blocks serve an important function in that they call attention to items and help you point the student to things you do not want them to overlook.
Blocks are also very engaging, and they can be good calendars, or even engaging content or activities.
