What is a Gantt chart and how is it used?

• A. A network diagram showing dependencies.
• B. A histogram of cost variances.
• C. A bar chart showing task durations and sequencing over time; it provides a visual timeline of activities and milestones.
• D. A risk heat map for mitigation options.

Answer: (C)

A Gantt chart is a bar chart that maps tasks against a calendar, with each task shown by a horizontal bar. The left edge marks when the task starts, the bar length indicates its duration, and the right edge shows when it ends. Tasks are listed in rows, so you can see the order and how activities overlap. Dependencies are often shown with connecting lines or arrows, illustrating which tasks must precede others and how sequencing unfolds. Milestones appear as special markers on the timeline to highlight key dates.

This visualization is used to plan the project schedule by laying out tasks, estimating durations, and defining how tasks relate to one another to create a feasible timeline. During execution, you update progress on the bars to reflect what’s finished, giving a quick view of whether the project is staying on track. It’s also a communication tool, helping stakeholders grasp the timeline and current status at a glance, and it aids in spotting timing conflicts, potential bottlenecks, and opportunities to adjust sequencing or resources. Baselines can be saved to compare actual progress against the original plan, making it easier to manage and report on schedule performance.