What is noise?

Noise, in the context of technology and information theory, refers to unwanted or undesirable signals or data that interfere with the clarity or accuracy of the intended signal. It can manifest in various forms, such as audio noise in sound recordings, visual noise (e.g., static) in images or video, or electromagnetic interference in communication systems. Noise reduction techniques are commonly used in many applications including audio and video processing, data transmission, and medical imaging, to improve signal quality and performance. In machine learning, 'noise' can refer to irrelevant or misleading data points that can negatively impact model training.