Safari Books Online is a digital library providing on-demand subscription access to thousands of learning resources.
Even if you’ve created a custom calendar for the project and a resource is following that calendar, not every resource has exactly the same working schedule. First, you might need to account for a resource’s nonworking days like vacation days or days taken off for surgery or a maternity leave. Or, a resource might work a flexible schedule such as 7 a.m. to 2 p.m. rather than 8 a.m. to 5 p.m. In situations like these, you need to adjust the resource’s calendar to reflect the resource’s actual working schedule.
Whenever a resource’s specific calendar differs from the project base calendar, the resource’s calendar overrides the project base calendar. That is, Project schedules any task to which you’ve assigned a resource according to the resource’s calendar rather than the project base calendar.