Parametric CAD allows the user to control all variables across an array of documents. The list is pretty exhaustive but as an example your part, assembly and drawing files are all linked. Make a change in one and the others update automatically. Collision checking in an assembly will alert to part overlap, if it should occur. Each workspace has a design tree that allows you to rollback your design to make changes. Along with that you can add material qualities such as density and (in more sophisticated softwares even young's modulus and poisson's ratio). That's the basics. Rhino can't do any of that.