What IS This?

I was mowing the grass and in the small lawn right in front of our house, I saw a Mushroom growing, so I reached down and picked it, and then placed it on the front porch railing.  I did that because I didn't want Mushroom pieces scattered all over the lawn by the mower.  I forgot about it until the next day, but it was still there, so I photographed it.  Look at the delicate underside of this fungus!  This is beautiful!  So when researching this subject, I discovered that these things are called  "gills," which are defined as "wide and thin sheet like plates radiating from the stem"  Sounds about right!  So is it a Mushroom or a Toadstool?  Let's ask Wikipedia:  "A Mushroom or Toadstool is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground, on soil or on its food source.  Toadstool generally denotes one poisonous to humans."  "The term mushroom and toadstool go back centuries!"

This is a view of the whole plant. The gills produce microscopic spores which help the fungus spread across the ground.  What an astounding thing these fungi are!  And I only know this because a random one was growing on my lawn and I became curious.  BE SURE AND CLICK ON THESE TO SEE ALL THE DETAIL.