A dado is a channel cut throughout the width of a plank. It can be made with a dado blade set designed for a table saw or a router with a straightedge piece, or simply by building a series of cuts with just one circular saw or table saw blade. It is most often used in bookcase and cabinet construction as a way of attaching shelves or walls.
A via dado is cut from 1 edge of a plank to another. A stopped dado doesn’t reach completely to the opposite end.
Centre Sky Architecture Ltd
Dados on the ladder revealed here hold and support the measures.
Here you can plainly see the dado cut from the plywood shelves to allow for the partition.