Which term describes information that is not necessary or important?

The term that describes information that is not necessary or important is "irrelevant." In the context of information, something that is deemed irrelevant lacks significance in the matter being discussed or considered. It does not contribute meaningfully to understanding or solving a problem, and therefore can be set aside without detriment. Recognizing irrelevant information is crucial in various contexts, such as academic research, decision-making, and effective communication, where focusing on pertinent details is essential for clarity and efficiency.

In contrast, terms like relevant, essential, and critical indicate that information plays a necessary role or holds significant importance in a given context, which fundamentally distinguishes them from the concept of irrelevance.