Unlike other texts in the market, this second edition presents differential equations consistent with the way scientists and engineers use modern methods in their work. Technology is used freely, with more emphasis on modeling, graphical representation, qualitative concepts, and geometric intuition than on theoretical issues. It also refers to larger-scale computations that computer algebra systems and DE solvers make possible. More exercises and examples involving working with data and devising the model provide scientists and engineers with the tools needed to model complex real-world situations.