What is a dado used for in cabinet construction?

• A. A wider groove to accept a shelf or back panel.
• B. A narrow decorative groove.
• C. A groove for sliding a panel.
• D. A method to join edges without adhesives.

Answer: (A)

A dado is a wide groove cut across the grain to receive another piece, such as a shelf or a back panel, creating a strong, square joint. In cabinet construction, you cut the dado into the sides (and sometimes the rails) so a shelf drops into place and is supported along a broad bearing surface, or so a back panel can be seated securely and stay aligned. This setup provides structural stability and proper load distribution without relying on fasteners alone. A narrow decorative groove isn’t the same thing—decorative grooves don’t provide the same structural support. A groove for sliding a panel describes a track meant for movement, not a fixed seat for a shelf or back panel. And joining edges without adhesives refers to other joinery methods, not the specific shelf- or panel-support function of a dado.