The Project product family includes Project Standard, Project Professional, Project Server, and Project Web Access. Normally you would use Project Standard on the desktop, or the latter three in combination to form an enterprise project management solution.
One of the key distinguishing factors that separates Project from other list- keeping tools like Excel is that Project has a scheduling engine that can work with time.
Project includes several sophisticated templates that may provide you with a good start to a new project plan.
The main working space in Project is a view. Normally you have one or sometimes two views displayed at a time. The Gantt Chart view is the default and probably best known view in Project.
Project includes a large number of built-in reports. These are intended for viewing (but not editing) Project data.
You use calendars in Project to control when work can be scheduled to occur.