The purpose of a load balancer in network management is to distribute incoming network traffic across multiple servers, ensuring optimal resource utilization and enhancing application availability. By preventing any single server from becoming overwhelmed with requests, load balancers help maintain performance during peak traffic periods. They also improve redundancy, as if one server fails, the load balancer can redirect traffic to operational servers, minimizing downtime. Additionally, load balancers can optimize response times and help manage traffic based on specific criteria, like user location or device type, improving the overall user experience and reliability.