Accurately simulate control systems, hydraulics (including thermal effects), pneumatics, gaseous flow, thermal, electrical, mechanical, refrigeration, environment control, lubrication or fuel systems, and sampled-data/discrete-time behaviour. Engineering aircraft, vehicles, agricultural equipment, and other complex systems requires a systems-engineering approach in which not only the components and subsystems but the entire system as a whole is tested. Traditional build and test methodologies are time-consuming and expensive;and now more than ever, every industry is challenged to meet the conflicting requirements of increasing innovation while reducing cost and time to market. Dynamic systems, those systems whose behaviour as a function of time is important, are typically defined using first-order differential (or difference) equations. Easy5 simplifies the construction and analysis of such systems by means of a graphical, schematic-based application, offering a comprehensive set of pre-packaged "components", stored in application-specific libraries, to simplify the assembly and simulation of such systems. Systems engineers work within a familiar schematic drawing environment to add and specify simple, yet complex, connections between components in an intuitive, simple-to-use, multi-level hierarchical modelling environment.