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# Bar Groups

Jumping back to our previous example, we provided a `SimpleBar` with a xValue and a yValue `BarData` to our `BarSeries` class.

BarGroups are the building blocks of a BarChart. They define how your data will represented as a Bar Rod, and also provides styling options should you choose to customize your individual bars.

Right now, there are two types of `BarGroup`s you can use:

1. **SimpleBar** - draws a single bar of height representing the yValue.
2. **MultiBar** - draws a group of multiple bars with each bar representing their own yValues.