This book introduces? seven new encryption designs based on different methodologies such as: chaotic differential equations of integer and fractional-orders, nonlinear generalized chaotic maps, fractal geometry, mixing between the generalized Fiestel network and the Linear Feedback Shift Register (LFSR), and also a new encryption system based on the chess-based horse-move to generate the permutation matrix. Many standard images ?are discussed and evaluated using the international measures such as NIST.