carriage bolt

Also known as "coach bolt"

From Wikipedia -

"Has a domed or countersunk head, and the shank is topped by a short square section under the head. The square section grips into the part being fixed (typically wood), preventing the bolt from turning when the nut is tightened. A rib neck carriage bolt has several longitudinal ribs instead of the square section, to grip into a metal part being fixed."

Can be used a torque washer to reduce damage to the wood, and to facilitate easier installation and removal.