The term nanotechnology is employed to describe the creation and exploitation of materials with structural features in between those of atoms and bulk materials, with at least one dimension in the nanometer range (1 nm ¼ 10-9 m). In Table 1.1, we list typical nanomaterials of different dimensions. Properties of materials of nanometric dimensions are significantly different from those of atoms as well as those of bulk materials. Suitable control of the properties of nanometer-scale structures can lead to new science as well as new devices and technologies. The underlying theme of nanotechnology is miniaturization. The importance of nanotechnology was pointed out by Feynman as early as 1959, in his often-cited lecture entitled ‘‘There is plenty of room at the bottom’’. The challenge is to beat Moore’s law, according to which the size of microelectronic devices shrinks by half every four years. This implies that by 2020, the size will be in the nm scale and we should be able to accommodate 1000 CDs in a wristwatch, as predicted by Whitesides.