The task list view shows all the details of each task within a project.

The Gantt chart represents each task with a horizontal bar which indicates when the task was originally planned to start and end, the current estimated start and end dates and the % complete.

You can see from the above screen-shot that the project is starting to slip! This is depicted by the lower originally planned task bars which are displaced to the left of the upper task bars.
The Pert chart shows the dependencies between tasks.

The Resource usage view shows the % allocation of a resource to tasks within the project.

The holiday view shows the holidays for a resource.
