KevinF

There are different ways of joining the tubes of a frame together. You can either weld them together, or you can join them together by lugs (amoung other methods). Lugs are simply short sleeve-like metal things that you put the tubes into, and then the tubes are joined to the lug by means of brass, or some other metal with a lower metal point then steel. If you look at: http://www.waterfordbikes.com/2005/d.../ss22/over.php those silvery things at the tube intersections in the pictures are lugs.

Lugs are the original way of joining tubes; welding them used to weaken the metal too much. The issues with welding have long since been resolved. It's a matter of personal preference as to which is "better". I personally think lugged frames are gorgeous and that welded frames look like crap, but there are others who believe the opposite.