This is a sample railing section created using only tradional joinery techniques: mortice and tenon, collars, and rivets.
Mortice and tenon joints are created by passing a tenon, a projection off the end of a bar that is smaller in size than the parent bar, through a hole of the same apporximate size and shape called a mortice. The pickets are attached in this way.
A collar is simply a bar of metal that wraps around two or more bars to hold them together. The two scrolls are joined in this way.
A rivet is a small bar that passes through two or more bars and is headded on both ends. The scrolls are joined to the ring and the ring is joined to the two small pickets in this way.
This is a sample railing section made to show the difference between fabrication techniques and traditional joinery.