Although revolutionary when they were first introduced, Gantt charts today are the most commonly used planning and charting technique. In short, they are a type of bar chart that illustrates a project schedule in a time line format. They show us the start and finish dates of the work to be done, as well as the inter-dependencies between the tasks that make up the work as a whole. If you are new to project management, this article will go into the origins of Gantt charts, how and when are they used, and what their advantages are.
The origins of the Gantt Chart
According to Wikipedia, a Polish economist named Karol Adamiecki created a precursor to the Gantt Chart, called the harmonogram. Its use and adoption was limited however, because Adamiecki didn't publish his work until 1931. It is said that the Harmonogram was very popular among Polish and Russian engineers.
Henry Gantt, an American mechanical engineer, is considered to be the creator of Gantt charts between the years 1910 and 1915. He created many different charts, which he designed so that foremen or other supervisors could quickly know whether production was on schedule, ahead of schedule, or behind schedule. The term 'Gantt Chart' was coined by Wallace Clark in his book The Gantt Chart, A Working Tool of Management.
One of the first major applications of Gantt Charts was by the United States during the First World War. Under the leadership of General Willam Crozier, it was used to manage the production of small arms and ammunition and commercial shipping efforts.
From 1931 to 1936, Gantt charts were also used to build the world-famous Hoover Dam, and the interstate highways system in the 1950s, before being forgotten or rather being restricted to the engineering world.
But during the 1980s Gantt chart came back to the limelight because of the birth of the software development industry and programming. Today they are widely used and can be seen in project files, boardroom walls and project plans. A lot of modern project management software includes this critical function.
What does a Gantt chart consist of?
A Gantt Chart consists of the following:
- Timeline – it shows the duration according to hours, days, weeks, months and quarters
- Vertical lines – they divide the time into various units (hours, days, weeks or months) and a separate vertical dotted line indicating the current date
- Arrows – they show how tasks are dependent on one another
- Milestones – they show a due date, or the finishing of an important phase of a project
- Bars - they show the full duration of a task
- Bar colors – these are predefined colors that indicate if the tasks are active, overdue or completed
So, in a nutshell, Gantt charts display tasks as horizontal bars (of different colors) across a calendar, creating a visual representation of the project schedule, so stakeholders can check on progress with a quick glance.
The advantages and uses of Gantt Chart
A Gantt chart has infinite advantages, but one of the major ones is that they allow teams to define problems visually. On a single sheet of paper, you have all the list of work to be done, the schedule to maintain it, and the resources involved. A complex project can be distilled into a work breakdown structure with a clear schedule so that the tasks are easy to tackle. With a quick glance, all team members know what is to be done and by when, and so every team member is on the same page. It is an ideal tool for managers and planners who are visual thinkers and detailed-oriented.
Gantt Charts also allow project managers and stakeholders to grasp dependencies. These are the arrows between the bars, which show how each task is related to another. This is very useful if one task needs to be completed first before another task related to it can be tackled.
If you are interested to learn how Planisware solutions can help you produce interactive Gantt charts, get in touch!