Stem and Leaf plot

A stem and leaf plot is a visually appealing way of showing a  fairly large numerical data set.  The stem, represents a defined group of leaves, or the individual pieces of data.  This stem and leaf plot shows the heart rate of 21 students after 1 minute of jumping jacks.  each stem defines 10  units of heart rate, starting at 60 and ending at 150.  As you can tell, the majority of student heart rates fall between 80 and 120 beats per minute

http://www.geo.utexas.edu/faculty/barker/kempter/rbtephra.html