Port is the opposite of starboard in nautical terminology. The port side of a boat is the left side, and boats should display a red light on the port side. The starboard side of a boat is the right side, and here there should be a green light. That way boats can know, in the dark, on which side another boat will pass, and going in which direction.

Picture it in your mind.

The Custodian informs me that the port side was originally so named because ships loaded cargo from that side when tied up, hence, "the side facing the port." Cool, huh?

If you have trouble remembering which is which, I have a mnemonic which works for me: On one side are all the short words:

  • left
  • port
  • red;
And on the other, the long:
  • right
  • starboard
  • green.