The ID field contains the identifier number that Microsoft Office Project automatically assigns to each task or resource as you add them to the project. The ID indicates the position of a task with respect to the other tasks or a resource in relation to other resources.
There are several categories of ID fields.
Data Type Integer
ID (task field)
Entry Type Calculated
How Calculated As you create tasks, Project automatically assigns the next number in the sequence of tasks as listed. This becomes the task ID.
Best Uses Use the ID field in a task view when you want to display or filter the task ID.
Example If you have three tasks entered in sequence, their task IDs are 1, 2, and 3. If you insert a new task between task 2 and task 3, the inserted task becomes task 3, and the previous task 3 becomes task 4.
Remarks When you insert, move, or delete a task, Project automatically updates the ID numbers so that the ID numbers always reflect the current task order. After deleting or moving tasks, if you want to return tasks to their original order, use the Unique ID field instead of the ID field.
ID (resource field)
Entry Type Calculated
How Calculated As you add resources, Project automatically assigns the next number in the sequence of resources as listed. This becomes the resource ID.
Best Uses Add the ID field to a resource sheet when you want to display or filter the resource ID, which indicates the resource order, or sequence.
Example If you have three resources entered in sequence, their resource IDs are 1, 2, and 3. If you insert a new resource between resource 2 and resource 3, the inserted resource becomes resource 3, and the previous resource 3 becomes resource 4.
Remarks When you insert, move, or delete a resource, Project automatically updates the ID numbers so the ID numbers always show the current resource order. After deleting or moving resources, if you want to return resources to their original order, use the Unique ID field instead of the ID field.
