Hysteresis is a phenomenon in which the output of a system depends not only on its current input, but also on its history of past inputs. In other words, the system's current state is influenced by its past states. Hysteresis can be seen in a variety of systems, including magnetic materials, biological systems, and economic systems. It is often characterized by a lag or delay in response to changes in input. Research in hysteresis seeks to understand the mechanisms underlying this phenomenon and its implications for various fields. This research often involves studying the dynamics of hysteresis loops, developing mathematical models to describe hysteresis behavior, and exploring applications of hysteresis in areas such as materials science, control systems, and economics.