A combination of measurements and modeling is often used when dealing with engineering problems. When taking measurements, engineers design and set up laboratory equipment to produce data which are collected and analyzed. When modeling, engineers work to understand the theories and principles underlying the physical phenomena, and write or use computerprograms to perform virtual experiments as an aid to ensure that results from the physical experiments are reasonable. Mathematical models for engineering applications, such as in the areas of finite elasticity and inverse kinematics, are often expressed in terms of systems of nonlinear equations which are difficult to solve. There is a problem with uniqueness and existence because a nonlinear system can have multiple solutions or no solution at all. When engineers are conducting numerical research, they either write their own programs or use available computer packages to solve nonlinear systems. Numerical analysis is at the core of both methods, and is directed towards developing and improving the mathematical algorithms required to perform the associated calculations