As you start this applet, you'll see six different ways of displaying the same set of grouped continuous data:

1. a table of frequencies
2. a frequency diagram
3. a frequency polygon
4. a table of cumulative frequencies
5. a cumulative frequency diagram
6. a boxplot (box-and-whisker plot)

The intention is help you understand the relationship between these displays, by playing around with the program.

You can click and drag on the little red circles on the vertical axis. Moving them up and down changes the frequencies in the different intervals, and all three displays change.
By ticking or unticking the options at the bottom of the screen, you can focus on different aspects of data display.
Some calculations are also shown, relating to the median and quartiles, and an estimate of the mean of the data.
You can look at some common distributions by choosing from the drop-down menu at the top of the page.
There is much to look at, but by changing the frequencies you can get an insight into how each display changes, and how the calculations are made. Play around!