But a PERT (Program Evaluation and Review Technique) uses a graph to show the relationships between tasks + time frames. They are better to help identify relationships rather than progress of tasks over time.
Some Key elements of a PERT diagram:
Ø Activities ( activities within a project & their dependencies)
Ø Events ( Beginning or the end of a task)
Ø Independency of tasks
Ø Critical path ( sequence of dependent events who have the sum of longest duration)
Ø Slack time ( events not on the critical path that does not affect the timing of other tasks, these tasks can fall behind schedule that has no impact on the completion date of said project)
If you would like to create your own Gantt or PERT you can try them at the following links.
project kickstart or minuteman-systems