While there are many spatial/frequency domain watermarking techniques, optimisation is a commonly encountered mathematical problem in data security related issues. The research on new embedding domains, hardware implementations and bio-inspired algorithms for optimisation problems is on rise as natural computing is able to solve computationally complex problems. This book covers the introduction of and state-of-the-art watermarking techniques developed in various domains along with their hardware implementations explaining how bio-inspiring techniques can find optimum solutions in relevant issues. It also include the applications, challenges faced by such algorithms and future research.