Cooked foods and leftovers should always be kept in airtight containers and refrigerated. Any type of food, whether raw or cooked, should never be left for more than four hours at room temperature. Food poisoning becomes a risk when food is left out, especially in hotter temperatures.
Single yarns of the spun type, composed of many short fibres, require twist to hold them together and may be made with either S-twist or Z-twist. Single yarns are used to make the greatest variety of fabrics.
Synthetic fibers and fabrics are all made from a type of polymer but they each have unique properties and characteristics making them useful for specific applications. The fibers and fabrics may include a variety of materials and may feature a blended, fibrous structure produced by copolymerization.