Hanging beams carry ceiling joists only, are held upright at their ends and bear on the full plate width (over a stud or stiffened plate from 3.0 m span); counter beams carry hanging beams on ledgers or hangers; combined strutting/hanging and strutting/counter beams carry roof and ceiling loads with strutting beam end supports; strutting beams carry roof loads only, bear on full plate width over studs supporting concentrated load or stiffened plates, have 25 mm initial clearance to the ceiling at midspan, and need alternative support where the end is cut down too far.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.