Informatory signs
Informatory signs are RECTANGULAR or square and usually blue. They tell you what is available rather than what you must do.
They cover services and destinations: hospital, first aid, telephone, petrol pump, eating place, rest place, parking, bus stop, police post, and route or direction signs.
On a highway the direction boards are green.
Getting the three shapes straight is worth more than memorising every sign: triangle warns, circle orders, rectangle informs.