The term "traditional" refers to the fact that each piece of glass
has a metal frame (usually brass) (usually about one inch wide)
surrounding it. Many years ago, this was the only style available.
After manufacturers figured out how to make the other "clear-view"
style, that variety became far more popular, but many people still
like the Traditional appearance.
JDoor's
Fireplace Door Selector Page is at:
http://mb-soft.com/juca/info/doors/firedoor.html