Tasks are things to do, a “point in time” (no duration), such a prepare meeting notes, set up conference room. They can be set in a future and they have dates and statuses. You can have assigned to yourself or that someone else has assigned to you.
Events are meetings (i.e. sales meeting on the 10th from 2pm to 3pm with Fred & Wilma), so they have a start time, an end time, a location, and invitees (tasks can’t).