What does a Gantt chart have to do with a harmonogram?
The origin of the Gantt diagram or Gantt chart reaches back one hundred years. And it was in Poland: because there Karol Adamiecki, a Polish engineer, developed a diagram with bars so he could better plan his projects, around the year 1890. He named this idea the harmonogram or harmonograph. Unfortunately, he only published his work in Polish and Russian, so that the Western world hardly noticed. And so it happened that Henry Gantt, an American engineer, developed a similar concept about fifteen years later and brought the idea to the West. That is why this type of diagram is now known as a Gantt chart or a Gantt diagram.