How do I read the results from a [Dunn][1] [test][2]? Specifically, what do the values in the table below tell me? 

I have non-parametric data in 4 groups, and I first did a Kruskal-Wallis test to confirm that the groups' distributions were dissimilar from one another and the aggregate dataset. I then used this Dunn test to see which groups were dissimilar from one another, and which were not. 

    dunn.test(data, g=area, kw=TRUE)
    Kruskal-Wallis rank sum test

    data: x and area
    Kruskal-Wallis chi-squared = 1730.4401, df = 3, p-value = 0


                            Comparison of x by area                            
                                (No adjustment)                                
    Row Mean-|
    Col Mean |          A          B          C
    ---------+---------------------------------
       B |   20.62310
         |     0.0000
         |
       C |   26.66519  -0.087499
         |     0.0000     0.4651
         |
       D |   39.09084   7.401256   9.469204
         |     0.0000     0.0000     0.0000

Thanks for your help!


  [1]: http://cran.r-project.org/web/packages/dunn.test/dunn.test.pdf
  [2]: http://stats.stackexchange.com/tags/dunn-test/info