whiskers in boxplot - still confused

["Danni Wang" <liuwang94710@hotmail.com>]

Dear Group,

There are some old discussions about how whiskers are drawn in boxplot(
). But it seems not answer my puzzle.

According to the help file, whiskers are drawn to the nearest value not
beyond a standard span from the quartiles, where the standard space is
defined as 1.5(inter-quartiles). 

So, the whiskers cover a span of 1.5(inter-quartiles). My puzzle is from
what quartiles, median, or others?  

Thanks.

Danni