It is a brand of 3D, there are the following:
RealD (Some times called Disney-3D as well as a few variants)
IMAX-3D
3D
I find that RealD is the one that causes me the fewest issues. It is easy to tell the difference, RealD is the one that gives you the 3-D glasses that you can keep or throw away (they are smilar to the ones used in the parks, but not on Star Tours, just modified a little). The other methods have reusable glasses and tend to cause more issues, especially with motion sickness, which is why I was surprised to see that they didn't use RealD on Star Tours and use glasses similar to those used in the 3-D films in the parks, just modified for RealD.
Also, I am sure this is obvious, but do not get a D-Box seat at a 3D movie if motion sickness is an issue for you (mine is headaches from that long of a 3D film).