What does the soccer blue card mean?

Answer 1

The blue card in soccer means that the player it has been issued to, must serve an immediate penalty suspension. Most suspensions are 2 minutes. The blue card is usually used when a field player handles the ball with his hands while in the goal.

Answer 2

There is no such card.

This is a perpetual myth that refers to the, apparently common, case when a referee quickly shows his glossy yellow or red card on television under lights. The glare of the lights often makes the card appear white on camera.

Answer 3

a green card is just a warning