Network performance monitors are tools used to assess the efficiency and reliability of a computer network. They track various metrics such as bandwidth usage, latency, and packet loss to ensure that the network operates smoothly. By identifying issues in real-time, these monitors help network administrators maintain optimal performance and troubleshoot problems quickly. These monitors can be software-based or hardware devices, and they often provide visual dashboards for easy interpretation of data. Common features include alerts for performance degradation and reports that help in planning for future network capacity. Popular examples include SolarWinds, Nagios, and PRTG Network Monitor.