Training data refers to large, organized datasets used to teach artificial intelligence (AI) and machine learning models how to recognize patterns, make predictions, or perform specific tasks. In cybersecurity, training data often includes examples of both normal and malicious activities, such as network traffic logs, emails, or files. By exposing AI systems to this data, they learn to identify threats, detect anomalies, and improve their accuracy over time. The quality and diversity of training data are critical; biased or incomplete datasets can lead to poor model performance or security risks. Regularly updating training data helps maintain robust and effective cybersecurity defenses.