How do Gantt charts help managers track production progress?

"Named after their originator, Henry Gantt, Gantt charts are bar graphs plotted on a time line that show the relationship between scheduled and actual production. In the example shown in Exhibit 10.9, the left side of the chart lists the activities required to complete the job or project. Both the scheduled time and the actual time required for each activity are shown, so the manager can easily judge progress. Gantt charts are most helpful when only a few tasks are involved, when task times are relatively long (days or weeks rather than hours), and when job routes are short and simple. One of the biggest shortcomings of Gantt charts is that they are static. They also fail to show how tasks are related. These problems can be solved, however, by using two other scheduling techniques, the critical path method and PERT."