These are names used for icing, fondant or sugarpaste that can be rolled out with a rolling pin and then used to cover and decorate a cake, you can also make edible decorations with it too.
Here are what a few of them look like….
Asda call it White Icing
Dr Oetker call it Regal Ice Ready to Roll
Renshaws call it Regal Ice or Decor-Ice this is good quality Professional Icing bought from Cake suppliers.
Cake stores sometimes have their own brand and call it Sugarpaste.
These are all the same product but just using different names and colours.