option is used to apply zero X-displacement boundary conditions.
The Restrain X option is used to apply zero X-displacement boundary conditions.
The nodes will be free to move in the Y direction only. The X displacement will be fixed at zero throughout the analysis.
Nodes restrained in the X direction are indicated by vertical "roller" symbols, when Restraints are displayed, as configured in the Display Options dialog.
See the Applying Restraints topic for information about applying restraints.