The areas of nanotechnology include fabrication and application of materials, devices, and systems at nanometer scales (one billionth of a meter, 10-9 m, or nm) as well as characterization of their special physical, chemical, and biological properties. Many of these properties vary with dimensions of the nanomaterials or nanostructures. The huge application potential inherent to such varieties justifies a new thrust to better understand the fundamentals from which one may gain control of the rules for materials or device designs and fabrications. The vast areas of application range from machinery, materials, chemistry, optics, metrology, military, energy, environment, biology, medicine and so on. In what follows, brief introductions are provided concerning the development in some of these areas. 

• Communications and optoelectronics: wireless and optical communications
• Precision machinery and micro(nano)-electromechanical systems (MEMS or NEMS)
• Materials and Chemical Engineering: nanomaterials and optoelectronics-specific chemicals
• Biomedical technology: genetic engineering and Chinese herbal medicine
• Sustainable developments: resource preservation and sustainable environment

When the dimensions of a material structure diminish to nanoscale, a large fraction of the atoms are exposed, hence becoming the so-called surface atoms. As a result, the physical and chemical properties of the nanostructures would be more surface-sensitive, namely, less chemically stable, and could become catalytic, making the nanostructures less durable for practical applications. The electrons in the small structures would tend to exhibit more conspicuous quantum effects as manifested in the localization and interference of the electron waves. When all these happen, quantum tunneling would make electrical insulation almost impossible. But, in any event, the traditional fundamental physics and chemistry may now not be sufficient any more to describe the newly composed nanomaterials.

Consequently, the primary challenge to take on is to seek new chemically stable nanomaterials of known physical and chemical properties. Carbon nanotube is one of the most widely known new materials discovered or invented at the dawn of nanotechnology. It has been the thinnest tube found in nature so far. It exhibits peculiar thermal and electrical conductivities, excellent mechanical strength and toughness, and is chemically stable. It is commercially applicable to producing batteries and TV or PC displays.

Furthermore, nano biotechnology has also been able to create or manipulate biological or biochemical materials or systems at atomic or molecular levels. Nanosensors used to investigate biological entities or track down diseases, such as those based on biological chips and other biological materials, will not only contribute to medical diagnosis, disease tracking and treatment, but also to the controls or manipulations of cellular genetics.

Nanotechnology aims to fabricate materials and control their properties by manipulating the most fundamental unit of matter at atomic or molecular levels in composing new materials or machinery of very tiny structures or dimensions. Commitments to the nanotechnology are an essential step toward fulfilling the demand of device miniaturization and more efficient use of resources in the human passage to reaching their ultimate socioeconomic objectives.