The hammer beam truss is more complex than other truss types. It is a beautiful truss, however, and also has the advantage of using shorter pieces of wood. The truss is composed of the hammer beams (red), hammer posts (blue) and hammer braces (green).
In this example, a through-tenon connects the hammer beam to the hammer post. A clever notch in the hammer beam makes for an extremely strong connection to the rafter. And all the other traditional mortise and tenon joinery is secured with hardwood pegs.