This product is vinyl fabric with knit woven backing.
Color is a matter of opinion. Your screen may portray the colors differently than they actually are. The photos are a good depiction of what you will get, please keep in mind different production runs can vary slightly between rolls. The name of the color is to give you a category and reference.
The sizes are sold as stated. Usually you get more than what is stated but is guaranteed to be at least the size that is sold.