the carriers in the direction normal to the ?lm becomes quantized leading to the quantum size e?ect. Such systems ?nd extensive applications in quantum well lasers, ?eld e?ect transistors, high speed digital networks and also in other low dimensional systems. In quantum wires, the carriers are quantized in two transverse directions and only one-dimensional motion of the carriers is allowed. The transport properties of charge carriers in quantum wires, which may be studied by utilizing the similarities with optical and microwave waveguides, are currently being investigated. Knowledge regarding these quantized structures may be gained from original research contributions in scienti?c journals, proceedings of international conferences and various - view articles.