Behind the scenes of your timeline are an interactive set of features, or rules, that determine how tasks are scheduled. This set of features is often referred to as the scheduling engine.
A partial list of scheduling features or rules include:
Project Start Date
Scheduling From the Project Start Date or Project Finish Date
Calendars
Schedule Selections in Options
Task Type (Fixed Duration, Fixed Units, Fixed Work) crossed by Effort Driven (Yes or No)
Resource Assignments
Task Mode (Manually or Auto Scheduled)
Task Constraints
Links or Dependencies