Could be real stone, ribbed marble, but I'm guessing man made.
In hot climates like the photo suggests you'd take off footwear at the door.
Soles of your feet are non-slip.
Cool marble is lovely.
In-laws in Malaysia have marble floors throughout the ground floor, and even wearing socks isn't a slip problem (but you sweat & could get foot rot and quickly learn not to).
Though dress shoes with new leather soles are a bit slippery on marble.
