Q: What are the metal grids in my windows called, and what do they do?

A: The metal grids in your windows are called muntins, strips of wood or metal separating and holding panes of glass in a window. Muntins are also called "muntin bars", "glazing bars", or "sash bars". Muntins can be found in doors, windows and divide a single window sash or casement into a grid system of small panes of glass, called "lights" or "lites".