Both are Activities — the Salesforce activity model is a polymorphic object linking to Accounts, Contacts, Opportunities, Cases, Leads, etc.
A Task is a to-do — something to be completed. Has a Subject, Due Date, Status (Not Started, In Progress, Completed, Deferred), Priority, and a related-to record. No specific time block. Tasks appear on a user's task list and can be filtered by Open/Closed.
An Event is a calendar entry — a meeting or appointment. Has a Subject, Start Date/Time, End Date/Time, Location, attendees (invitees from Salesforce User table or external email addresses), and a related-to record. Events appear in the calendar view and can sync with Outlook/Gmail/Google Calendar via Einstein Activity Capture or the legacy Salesforce for Outlook.
Key differences:
- Time: Task has a Due Date (single date); Event has Start + End (with time).
- Completion: Task is marked "Completed"; an Event just happens (or doesn't).
- Calendar: Events show on a calendar view; Tasks don't.
- Reminders: Both can have reminders.
- Sync: Events sync to external calendars naturally; Tasks sync less reliably (depends on email integration setup).
- Reporting: Both reportable but typically grouped on different reports — Open Tasks by User vs Calendar of Events.
A common pattern is to use Tasks for "follow-up actions" (call back next Tuesday, send proposal) and Events for booked meetings (demo scheduled Tuesday 2pm).