Dependency graphs can also be annotated with the resources required for each node or edge. Resources are estimated by summation, time is estimated by finding the critical path.

Gantt charts are a partial linearization of a dependency graph. People tend to fixate over the dates shown, allow schedule pressure to "correct" previous estimates, etc.

According to some early users of Gantt charts, they are a great tool for summarizing a plan, a terrible tool for developing and maintaining one.