Causal Systems

A causal system is one where the output depends only on current and past inputs, not future ones. In simple terms, it responds based on what has already happened, making it predictable and aligned with real-world processes. For example, a heating system that turns on after detecting a drop in temperature is causal, because it reacts to past or current conditions, not future ones. This property is important in engineering and signal processing because it ensures systems can operate in real time, using only available information to generate appropriate responses.