Charts enable you to visualize the metrics you are sending in to SignalFx.

SignalFx available chart types are the following:
Time chart is the only chart type that includes four different visualization options for SignalFx graphs (image below): Line Chart, Column Chart, Area Chart and Histogram Chart.

Just note that if you want to create Area Chart, you need to create a Time Chart Resource and set the property plot_type = "AreaChart" (more info here).