Dreams are often seen as highly significant. They can have many layers, and many interpretations. Yet scientists still don't know why we dream.

Even people who don't remember their dreams still have them. Tell us about your dreams, what you dream, when and why.

• Do you dream in colour or black white?
• Do your dreams feature sound?
• Have you mastered lucid dreaming - can you control what happens in your dreams?
• Do you keep a dream diary, and try to make sense of the images that you see?
• Can you make yourself dream of a specific person?
• Do you have nightmares that you can't wake up from?
• Do you 'act out' your dreams by talking or walking in your sleep?