Is there a difference?

How is training going? Well.

What I want to know is, is there a difference between 'step count' and 'mileage'?
I use a pedometer to count my steps each day because I was wondering how many steps I take at the dock when I'm working. I did measure my steps and input the information into the pedometer so its at least close to accurate for distance. Except, I don't always take a 'step' forward when I move my leg. I take many steps where I just lift my foot and set it back down, to relieve the pain. Yesterday I took 6634 steps but the day before I took over 13,000 during the day and there was a huge difference in the pain in my feet.
Linda uses a BodyBugg on her arm, it counts steps and calories and I don't know what all else. She wears it when shes doing all of her exercise classes, including kick boxing, spin and all others. I think this is giving her a false step count, since these aren't steps. Yes, shes moving but no, they aren't steps. I don't wear my pedometer unless I'm actually walking, all my spin classes, bike rides, etc are extra.
Just my rant.