Before pieces of glass can be permanently assembled, their edges must be wrapped in thin metal - either foil or came.
The foil, or "Tiffany," method uses narrow strips of flexible copper, with adhesive along one side, which is applied along the edge of the glass, then folded down, or "burnished." Copper foil is easier to work with, but not always as strong as metallic cames, so is usually used for smaller projects that need less support.
Came is most commonly made of lead, but zinc, brass, and copper cames are also available. Different cames provide different levels of support. Like foil, came is applied to the edges of the glass, but unlike foil, came has a groove into which the glass edge is inserted, rather than adhesive.