A.L.
Thomas has both. And on three different scales - the trains for each scale aren't compatible with each other.
I'm guessing you're thinking the one that can be set up with the play table? It's wooden - the manufacturer is Learning Curve. It has the most available pieces.
There is the portable system that is plastic. It used to be made by Learning Curve and was called "Take Along," but now it's made by Fisher Price and is called the "Take and Play" or something like that. It is smaller than the wooden set.
There is the "Trackmaster" set, also made by Fisher Price, that is also plastic. It is on a larger scale then the wooden Thomas set.
http://www.thomas-tank-engine.com/read/compare-the-differ...