The Task List window is located to the right of Diary mode. It is a to-do list with a set of very powerful features to help you keep track of your workload.
OfficeTalk lets you record one or more of the following attributes against each task:
A description of the task.
A priority.
A deadline.
Whether or not the task has been completed.
Detailed notes about the task.
Additionally, you may add any number of user defined fields to the task data type which means that you can store almost any data that you like with each task. For more information on adding user defined fields to tasks see Administering Custom Data.
More:
Scheduling Tasks into the Diary
Finding When a Task is Scheduled
Assigning a Task to a Microsoft Exchange or Microsoft Outlook User