You have four calendars, one for each category: Health & Fitness, Work, Learn and Life.

Your Events in each category are represented as dots on the calendar.

If you do not have a Buddy, no one else can see your calendars.

If you do have a Buddy, your Buddy can see your events for the category in which you are matched and you can see theirs. 

Example: If you have a Health & Fitness Buddy, they can see your Health & Fitness events, and you can see theirs.

Your events are dots, and your Buddy's events are represented as shapes.

Example: