Abstract The article concerns the problem of languages used in modeling and solving problems. Its framework stems from the distinction between two problem solving approaches – expert and interactive approach. The language choice is particularly important for the latter; we cannot solve a problem using a language that has not been used for the problem description. The text presents some arbitrarily chosen problem modeling languages, including computer supported ones. Special attention is paid to the SEQUAL and System Dynamics language.
Keywords: problem modeling and solving, formal modeling languages, expert and interactive approach to problem modeling, SEQUAL, System Dynamics language.