Charts provide a graphical representation of data. Values or data points are displayed in formats such as bars, lines, filled areas, and pie charts. These data points are grouped into series that are identified with unique colors. In many chart types, one data point from each series is grouped together by category across an axis. A chart can also have a title and a legend. Categories are plotted along the x-axis, values are plotted along the y-axis. A two-dimensional chart shows series next to each other, while a three-dimensional chart plots series along the z-axis.