Packet loss refers to the failure of one or more data packets to reach their intended destination across a network. This occurs when packets are dropped or discarded during transmission due to network congestion, hardware faults, software errors, or signal degradation. Packet loss can lead to reduced network performance, causing issues such as slow loading times, interrupted audio or video streams, and unreliable connections. Monitoring and minimizing packet loss is essential for maintaining the quality and reliability of digital communications.