Discrete Wavelet Transform (DWT) is extensively employed in functional as well as numerical analysis. The most significant advantage of this type of transform over more conventional wavelet transforms, for example Fourier transform, is its capability to present temporal resolution, basically meaning that it captures frequency as well as location (or time) information. The book provides a concise compilation of some of the latest variants of DWTs and their use in order to formulate solutions to a broad spectrum of problems transcending the conventional application fields of video/image processing and security to the comparatively novel fields of artificial intelligence, telecoms, medicine, and power systems. It includes comprehensive information regarding the traditional applications of DWTs in video resolution improvement, digital image compression and copyright security. Further on it provides information on the variants of DWT and their applications in modeling and simulation recognition of behavioral and physiological traits through human gait and facial images and for the purpose of evaluation of sedation and agitation in intensive care patients. The applications of wavelet transform for the optimization of power control systems is also highlighted efficiently. Furthermore, the book presents state-of-the-art examples and researches for the purpose of elucidating the use of DWTs in the demodulation of FM data in free-space optical control systems and in humanoid-robot vision systems.