You can create fully documented correspondence with your customers by creating activity records. You can organize and track activities:
Organize activities by the completion date, so that you know what you've performed and when.
Organize activities by type, priority, date due, or the reason for the activity.
Organize activities by status The state of a record or activity. For example, a case can be Active or Resolved, and an e-mail activity can have a status of Draft or Sent. Status is also used by workflow rules to determine when to move to the next stage in a workflow or sales process..
Review a list of activities that have been performed for a particular customer.
Associate an activity with an account, contact, lead, or opportunity.
Create mail merge documents.
You cannot set reminders for faxes, phone calls, letters, or campaign responses. Whether you can set reminders for tasks, e-mail messages, appointments, and service activities depends on whether you created the activities in Microsoft Dynamics CRM Online for Microsoft Office Outlook or in the Web application The version of Microsoft Dynamics CRM Online that works in Microsoft Internet Explorer.. More information: Manage Activities