The prefix "meso" means "in between" or "intermediate." Mesoscopic systems are those that are larger than atoms and yet very much smaller than the large-scale everyday objects that we can see and touch. They are 1,000-100,000 times smaller than the diameter of a human hair and they range in size from several hundred nanometers or billionths of a meter. That is why materials composed of mesoscopic parts are also known as nanostructures, and the technology based on these systems is referred to as nanotechnology. Since one nanometer is less than the width of 10 atoms in a row, mesoscopic systems are made up of less than a thousand atoms. Mesoscopic or nanoscale systems behave very differently from large-scale objects and they often have unusual physical and chemical properties. This makes them extremely interesting to scientists and engineers who hope that, by manipulating systems on the nanoscale, they...