A silicone baking mat is a mat made of laminated and ruberized silicone. Some have reinforced fiberglass fibers or a fiberglass mesh and those types of mats are not made to be cut, trimmed or used with any cutting intruments as the fiberglass can contaminate food. All silicone baking mats have a degree of high heat durabilty and some range up to 480 degrees F. down to minus 40 degrees F. That range covers everything from flash freezing to oven roasting.
These mats are often used for baking thin tuiles and for glass-type cookies. Their nonstick properties make them very useful for any sugar item and for cookies, tarts, etc. They can make any regular baking sheet have a non-stick bottom. They are hand-washed and dried and stored flat.