A Pie chart, often refered to as Circle Chart, is displaying data in the shape of a circle. Each section in the chart resembles a slice of a pie and they all add up to 100%. Any individual slice will display its portion of the whole.
The primary objective with a pie chart should be to compare each groups contribution to a whole.
While Pie charts can be harder to read than column charts, they remain a popular choice for small datasets.
Our brain finds it hard to interpret and compare the triangular shape of the slices. Especially when there are many slices or not next to each other. There are loads of discussions around the maximum number of slices. Our general recommendation is max 4 to make it easier for your audience to understand the message.