A chart style is a predefined combination of formatting elements such as colors and shape effects. For PowerPoint 2013, Microsoft provides a large assortment of chart styles to choose from.
To change the style for a chart, follow these steps:
Click the chart to select it.
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The Ribbon expands to include the three Chart Tools tabs.
Click the Design tab.
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The Chart Styles group displays the most commonly used styles for the chart type.
Select the style you want to use from the Chart Styles group.
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If the style you want to use isn’t visible in this group, you can click the More button to display a gallery of all available styles. (The More button is the down-arrow button at the bottom of the scroll bar that appears at the right side of the Chart Styles group.)