This chapter discusses generic attributes related to simulation modeling. Simulation languages have been developed because of the unique needs of the modeling community to have system routines to keep track of time, maintain the state of the simulation, collect statistics, provide stimulus, and control interaction. The chapter looks at five languages and discusses the aspects that they possess that aid in the simulation process. Simscript provides a discrete simulation modeling framework with English-like free-form syntax making for very readable and self-documenting models. The simulation program is composed of a set of Slam II network statements and detailed discrete event code (similar to GASP IV), which model the major computational aspects of a distributed database management system. Slam II is a combined modeling language providing for queuing network analysis, discrete event, and continuous modeling in integrated form. Queuing modeling provides the modeler with a view of systems being comprised of queues and services.