An adhesive is a compound that sticks or bonds two items together. Adhesives may come from either natural or man-made material. Some modern adhesives are extremely strong, and are becoming increasingly important in modern construction and industry. Examples of adhesives include adhesive tape, glue, and sticky-tac. Some adhesives are for temporary use, like sticky-tac or the adhesive on sticky notes. Others are for more permanent bonding of small items like gluing paper or building large pieces of furniture using construction adhesive.