It's a well known and established fact that when cats are not taking a nap, they are usually plotting to take over the world. Probably the only pastime they love more than doing those two things is soaking up the sun.
And they're not doing it to get their dose of Vitamin D. Cat's regular body temperature is higher than human's (102°), they are desert creatures that originated in the Middle East where they developed a high tolerance to the heat. They have a very high metabolism and a lot of energy goes to keeping them warm. That's why when they find a sunlit spot to lie down, they will, as it actually conserves their energy and offsets the drop in basal metabolism that comes with sleep shutting down certain processes in the body. That metabolic heat advantage is exactly why they love them some sun - or warmth - and can get in the most uncomfortable positions to get it.
Yup, cats and the sun have a very special kind of relationship - and Bored Panda made a compilation of pics to celebrate it. If your kitty loves lying down in the sunlight too, make sure to add a submission to our list.