The usual example used in teaching is Ansombe's Quartet: https://en.wikipedia.org/wiki/Anscombe%27s_quartet https://en.wikipedia.org/wiki/Anscombe%27s_quartet

The usual example used in teaching is Ansombe's Quartet: https://en.wikipedia.org/wiki/Anscombe%27s_quartet https://en.wikipedia.org/wiki/Anscombe%27s_quartet It consists of 4 datasets with the same summary statistics, but when plotted look very different. It's much easier to see the patterns in the plots than in the data table.