When you go to bed at night, snuggle up under the covers and get comfy, are you going to be sleeping on your back, front or side?
That's the question that's currently got social media in a bit of a spin, as people are divided over which sleeping position is the best one.
It all started on Monday, when a man named Allan Bell took to Twitter to share a photo showing 18 different ways to sleep in a bed.
Alongside the image, he wrote: "I'm a No. 9, which are you? (Also if anyone says they are a 13 just what are you doing lol)."
His post quickly went viral, garnering over 12,600 likes and more than 1,300 retweets.
It's fair to say Bell's fellow Twitter users had a lot of thoughts on the topic.
One person replied: "Whomever is 15 probably murders people during the day."
But in case you're wondering, a sleep expert did recently reveal the 'best' position to sleep in.
Neil Stanley, author of How To Sleep Well, revealed that the most common position for adults to sleep in is the foetal position, on the side with the knees tucked, with 41 percent of adults drifting off this way.
However, sleeping on your back is actually the "ideal position" as it can reduce pressure on the muscles and joints - as long as you don't have sleep apnoea or snoring problems.
He went on to say that sleeping on your front offers very little in terms of benefits.
Sleep counsellor Sammy Margo agreed with this, adding: "Try not to sleep on your front, it’s the worst position for deep rest.
"If you sleep on your side, put a pillow between your legs, as this aligns your hips so you’re less likely to be disturbed by back pain.
"I encourage patients to learn to sleep on their back, with a pillow under the knees. There’s less strain on your body, you don’t crease and age your skin and your night creams absorb and work better."