Seaming & Nipping Glass

Seaming glass actually strengthens the structure of the pane. Seaming refers to grinding the edge of the glass, relieving the sharp angle along the edge of the pane. Nipping the glass is essentially the same as seaming except it relieves the corner of the pane.
The strength of glass relates directly with the integrity of its surface tension. Creating a radius or chamfer along the edge or at the corner of a pane of glass transfers the shock of impact past the edge and across the surface of the glass greatly reducing the likelihood of fracturing the pane.
This also makes the glass safer to handle, because it is stronger and less likely to cut the person handling it.