Quote from Fireball76:

On one of my pinkie toes the nail is really thick and slightly yellow in color. Does any one know what the cause of this is. I don't think it was always this way, but it has been for years now. I usually trim it down in length and in thickness with toenail clippers. Is this a nail fungus? Thanks!

Yes, it is! Fungus will manifest itself with a yellowish discoloraiton in the nail plate as well as thickening of the plate - sometimes it will even crumble. You can get a prescription from your doctor for Lamasil or Sporanox.