(bright music) Schedules are essential tools for project managers to determine what needs to be done by whom and when. They are time-based roadmaps for the completion of project work. Project schedules include details of the work involved to complete the project, determining who will do which tasks, and a timetable of when tasks are expected to be completed and how much it is expected to cost. The documents used to create the schedule can be used to help manage changes to the work and plans. The project manager and the team should be familiar with the work included to complete the project. The order of work completion and the availability and costs of the resources required to complete the work should be incorporated into the project schedule. Limitations and constraints, such as time, money, or available resources, also need to be considered. Schedules need to have the right level of detail to be at their most effective. If detail is minimal, work may slip through the cracks. But if the level of detail is excessive, the schedule will be difficult to manage, and you may find yourself spending more time managing the schedule than other important work. Excessive detail could also make the team feel micromanaged, which could stifle creativity. So what's the right level of detail? In general, the scheduled project tasks shouldn't take less than a day or more than four to five weeks to complete. Knowledge work tasks such as computer programming, information technology, architecture, and engineering are recommended to take about three weeks. Projects that have physical products as their output, such as construction work performed by outside resources and vendors and projects with longer lead times to acquire necessary resources are recommended to have most of their activities scheduled around a month apart. This is because their tangible results are easy to verify and their progress is easier to track. A complete project schedule may appear in several ways. A Gantt chart uses bars to represent task completion times. Tasks are usually on the vertical axis, and the horizontal axis is a time scale. Modern Gantt charts include connecting arrows to show the dependencies of tasks. They also include information in tabular form. You could also use a milestone chart or plan to represent these factors. Milestone charts have information that lets project participants know who needs to do what and when.