Sugar is the generic name for sweet-tasting, soluble carbohydrates, many of which are used in food. The various types of sugar are derived from different sources. Simple sugars are called monosaccharides and include glucose, fructose, and galactose.
Salt is a seasoning, an essential nutrient, but also a very important preservative. Table salt is sodiumchloride combined with iodine sources (for nutrition), stabilizers for the iodine, and anti-caking compounds to make it pour by preventing it from absorbingwater from the air.