This is an interactive scatterplot that has two modes indicated by the top left boxes. While in the insert mode, whenever you click on the scatterplot a data point is inserted at the location you had your cursor where you clicked. The X and Y values of that location are presented in the upper right-hand corner. You can add up to 50 points of data.
Summary statistics are also updated.
The page starts in the insert mode. The second mode is the play mode. When you are in the play mode you can move your cursor on top of an existing data point in the scatterplot and it will be highlighted. By keeping the mouse button down, you can move that datapoint to any location in the scatterplot. All the summary statistics and graphics will be updated automatically.