What term best describes a situation where an application requires immediate responses to certain events?

The term that best describes a situation where an application requires immediate responses to certain events is critical operation. In computing, critical operations refer to processes that are essential for the functionality and performance of an application. These operations often involve real-time processing demands, where delays in processing could lead to adverse effects such as service disruptions, data loss, or safety risks, particularly in environments like financial services, healthcare, or emergency response systems.

In contrast, emergency processing typically involves a predefined set of actions taken during exceptional or urgent situations, not necessarily tied to the continuous functioning of an application. Routine functions represent standard operations that occur under normal circumstances without urgency, while event escalation refers to the process of prioritizing events based on severity or need for attention, but it does not clearly convey the immediate response requirement found in critical operations. Thus, the emphasis on immediate responses directly aligns with the definition of critical operations.