The chart type includes the following subtypes: line, bar, area chart, pie, and scatter.

It's a two dimensional visualization type, and is best used to represent time series data (daily/weekly values such as daily active users) and categorized values (for example, the number of sport clubs per city).

Pie charts can be used to show value distribution between different categories.

The following is an example of a line chart. This chart shows the number of user triggered events in Redash per hour in the past 3 days:

The following is an example of a bar chart, showing the number of queries per visualization type:

The following is an example of a pie chart, which uses the same query as the bar chart, but the visualization has been changed to pie:

The following is an example of a bar chart with stacking. This chart shows us the percentage of active Redash accounts, stacked by stage (source: redash.io):