- Use the links between tasks if the tasks must be carried out in a specific order.
- Use the fixed links between tasks if the completion of tasks must follow a specific order and if a fixed duration must be respected between the completion of two tasks.
- Use the milestones if certain tasks are an important step in your project.
For more information, see the article dedicated to links and milestones.
Note: you cannot link tasks that do not belong to the same project.