| Name | Description |
| ActivityType | Gets the ActivityType of this activity. |
| Categories | Specifies categories associated with this activity as a comma separated list of category id's. |
| DataItem | Gets the underlying data item if any. |
| Description | Gets or sets the text associated with this activity. |
| Duration | Gets the duration of the activity. |
| End | Specifies the time in UTC when the activity ends. |
| EndTimeZoneId | The time-zone id associated with the activity. The Start and End times are always in UTC. |
| Error | Gets or sets the error if any associated with the activity. |
| Id | Gets or sets the appointment Id. |
| IsLocked | Specifies whether the activity can be modified in the UI. |
| IsOccurrence | Returns true if the ActivityBase is an occurrence of a recurring ActivityBase (read only). |
| IsOccurrenceDeleted | Gets or sets a value indicating whether the occurrence has been deleted. |
| IsRecurrenceRoot | Returns true if the ActivityBase is a recurring ActivityBase with a define set of RecurrenceBase rules (read only). |
| IsTimeZoneNeutral | Specifies whether the activitiy's times are time-zone neutral or "floating". |
| IsVariance | Gets or sets a value indicating if the activity is a variance of an occurrence. |
| IsVisible | Gets or sets whether the activity is visible. |
| IsVisibleResolved | Gets the resolved value indicating whether the activity is visible. |
| LastModifiedTime | Gets or sets the time in UTC when the activity was last modified. |
| MaxOccurrenceDateTime | A date-time value that's equal or greater than the date-time of the last occurrence of the recurring activity. |
| Metadata | Returns a MetadataPropertyValueStore object that's used for storing and retrieving metadata information. |
| OriginalOccurrenceEnd | Only applies to occurrences of a recurring activity. Specifies the original date-time as it was generated by the recurrence. |
| OriginalOccurrenceStart | Only applies to occurrences of a recurring activity. Specifies the original date-time as it was generated by the recurrence. |
| OwningCalendar | Gets or sets the calendar to which this activity belongs. |
| OwningCalendarId | Gets or sets the id of the calendar to which this activity belongs. |
| OwningResource | Gets or sets the owning resource. |
| OwningResourceId | Gets or sets the owning resource id. |
| Recurrence | Specifies recurrence rules. |
| RecurrenceVersion | Specifies the recurrence version. |
| Reminder | Specifies the reminder information. Default value is null. |
| ReminderEnabled | Specifies whether the activitiy's reminder is enabled. Default value is false. |
| ReminderInterval | Specifies the reminder interval. |
| RootActivity | Gets the root activity. Only valid if this activity is an occurrence or a variance of a recurring activity. |
| RootActivityId | If this activity is an occurrence or a variance of a recurring activity, gets the id of the recurring activity. |
| Start | Specifies the time in UTC when the activity starts. |
| StartTimeZoneId | The time-zone id associated with the activity. The Start and End field values are always in UTC. |
| Subject | Gets or sets the subject associated with this activity. |
| VariantProperties | Properties of a variance that have been modified and thus will not be synchronized with the root activity. |