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Introduction to Gantt charts

While the WBS shows the structure of a project, a Gantt chart helps to define how activities flow in your project.

Should the activities be carried out in sequence? Or can there be parallel streams of activity? To clarify such questions, it helps to plot a Gantt chart, which represents a schedule of the project.

Preparation of a brochure for the company event, Gantt chart. ID A, Identify the contents, no predecessors, duration 2 days, bar from 0-2 marked complete, arrows to B and D. ID B, Draft the texts, predecessor A, duration 3 days, bar from 2-5, activity from 2-4 marked complete, 4-5 marked planned, arrow to B. ID C Revise the texts, predecessor B, duration 2 days, bar from 5-7 marked planned, arrow to E. ID D, prepare the graphics, predecessor A, duration 3 days, bar from 2-5, activity from 2-4 marked complete, 4-5 marked planned, arrow to E. ID E, Create a sample, predecessor C and D, duration 3 days, bar from 7-10 marked planned, arrow to F. ID F, Validate the sample, predecessor E, duration 2 days, bar from 10-12 marked planned, arrow to G. ID G, Print, predecessor F, duration 2 days, bar from 12-14 marked planned. Gantt chart for the company event brochure

A Gantt chart shows all the activities of a project and their duration as a bar chart, with the timescale at the top or bottom. The activities are placed on the bar chart in sequence, starting in the top left-hand corner, and following their precedence rules. The column named Predecessors indicates the immediate predecessors of each activity. The activity bars can be connected to earlier and later activities with arrows, to show their dependency on each other. A Gantt chart is often the tool a project manager uses to make a rough estimate of the time that it will take to complete the activities and the whole project. Sometimes it is useful to start by working back from the target deadline for completion of the whole project. In this way, it soon becomes apparent if the timescale is too short or unnecessarily long.

As well as showing activities, you can use a Gantt chart to indicate milestones and deliverables at key points on the chart. This practice is quite common and shows how activities lead to the creation of deliverables and the achievement of milestones. In many cases, the possibility of representing deliverables and milestones depends on the tool used to create the Gantt diagram.

In the next few steps, you will discover some tools you could use to do this: an Excel template and some online tools.

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This article is from the free online course:

Business Fundamentals: Project Management

The Open University