The role of a load balancer in web services is to distribute incoming network traffic across multiple servers. This process enhances the overall performance, reliability, and availability of applications by preventing any single server from becoming overwhelmed with requests. Load balancers help optimize resource use, improve response times, and provide redundancy; if one server fails, traffic can be rerouted to others. This technology is critical for maintaining smooth user experiences in high-traffic environments, such as e-commerce websites.