A square area chart—also known as a waffle chart—is a square display. They often consist of a 10×10 grid containing 100 individual squares. The squares are then coloured based on the data that’s being visualised. The chart gets its food-based name from its resemblance to a tasty waffle. (Sometimes this type of chart is referred to as a “unit chart,” although that term applies more appropriately to a broader category of visualisations, which tend to use discrete icons, rather than squares, to represent the values.)
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