Understanding Activity Party and Acitivity pointer from tables prospective

 Whenever you create any activity in Microsoft Dynamics CRM,

1. ActivityPointer record is created
2. Couple of ActivityParty records are created .

ActivityPointer Table
ActivityPointer.ActivityTypeCode attribute defines the type of the activity. The possible values for this attribute are defined in the Activity Type (activitypointer_activitytypecode) option set.

Values of ActivityTypes include

Appointment
Email
Fax
Case Resolution
Letter
Opportunity Close
Order Close
Phone Call
Quote Close
Task
Service Activity
Recurring Appointment
Campaign Response
Campaign Activity
Bulk Operation

ActivityParty Table

An activity party represents a person or group associated with an activity. An activity can have multiple activity parties.

There are 11 activity party types in Microsoft Dynamics CRM.

Activity party types are

Sender
ToRecipient
CCRecipient
BccRecipient
RequiredAttendee
OptionalAttendee
Organizer
Regarding
Owner
Resource
Customer