Question about outer edge of discs




I’m new to the forums, and I have a question that has been on my mind for nearly week now. I’m hoping someone could kindly explain this to me.

I noticed a silver shiny aluminium silver ring around the circumference of Playstation 2 CD/DVD’s. It appears on both sides of the disc near the very outer edge. Is data writte on there or is it just a border around the disc.

So, does it contain data? Or is it just a border around the edge of the discs?