Prohibition signs are there to tell you not to do something. They are a danger sign, telling you that it is not safe to proceed. And what colour makes you think of danger? Red of cour… See more

Mandatory signs are there to tell you to do something. Consider these the opposite of prohibition signs. Mandatory signs are round. The pictogram is white on a blue backgroun… See more

Warning signs are there to warn you of dangers. Unlike the two previous signs, they don't tell you not to do something, or to do something. They simply aim to make you aware … See more

Safe condition signs can usually be followed to safety. And what colour better represents safety than green? That's right, they are green! These signs are rectangular or square. … See more