Hi C.,
My daughter is 19 months and we've had a small potty on the floor in her bathroom for quite some time now. We talk about it occasionally and I always tell her what I'm doing when I use the bathroom, especially flushing, washing hands afterward, etc. They are not too young to understand the concepts and I think you should have it available, first, so she can get comfortable with it before you start to potty train... but also, so that if she's curious about it, you can introduce the concepts slowly at first and let her experiment with it before training. My daugther went through about a week or two in June (after visiting with her older cousin) where she sat on the potty after dinner and she even went #2 in it twice. As of now, she's not showing any interest, even though she knows the concepts, so I'm not pushing her to use it unless she wants to. We've had a couple of occasions where she's gone #2 in the tub, so I'm trying to get her accustomed to letting me know if she thinks she has to go before we take her bath. It's a process, for sure. Be patient and just let her get comfortable with it and go from there. Every child is different and although most people recommend trying to train at 2, your child may be ahead of, or behind that learning curve age. Either way, it's totally normal.
I bought a very inexpensive Circo potty that also doubles as a step stool for brushing her teeth. When she wants to, she lifts the lid and sits down, with a book in her hands... it's hilarious!
Good luck!
K.