Which Type of Chart Is Better?
Although a Gantt chart offers a valuable
snapshot view of the project, PERT
charts are more useful for scheduling,
monitoring, and controlling the actual
work. With a PERT chart, a project manager can convert task start and finish
times to actual dates by laying out the
entire project on a calendar. Then, on
any given day, the manager can compare
what should be happening with what is
taking place, and react accordingly. Also,
a PERT chart displays complex task patterns and relationships. This information
is valuable to a manager who is trying to
address high priority issues. PERT and
Gantt charts are not mutually exclusive
techniques, and project managers often
use both methods.
Figure 3-7 shows both chart types. The
top screen is a Gantt chart with 11 tasks.
The PERT chart in the bottom screen
shows the same project, using a separate
box for each task instead of a horizontal bar. Although they both show the task patterns and flow, the PERT chart boxes can provide more detailed information, such as task duration, start date, andfinish date. You
will learn how to create PERT charts in following sections.