The same directions could be printed on a yellow or an orange sign. Why is it important to recognize the difference if you're just going to be doing the same maneuver anyway?

Orange signs are construction, meaning they require a certain speed to pass through. However, yellow are warnings and suggestions for something ahead that doesn't legally require you to be below any certain speed, only showing a guideline for how you should drive.

the cat said meow. the police should not have shot it.