Load Balancer
A load balancer is a networking device or software component that distributes incoming network traffic across multiple servers or resources to ensure no single server becomes overwhelmed, improving availability, reliability, and performance. It acts as a reverse proxy, routing client requests to backend servers based on algorithms like round-robin, least connections, or IP hash, and can provide health checks to detect and avoid failed servers. Load balancers are essential for scaling applications horizontally and handling high traffic volumes in distributed systems.
Developers should learn and use load balancers when building scalable web applications, microservices architectures, or any system requiring high availability and fault tolerance, such as e-commerce sites, APIs, or cloud-based services. They are crucial for distributing traffic during peak loads, enabling zero-downtime deployments through rolling updates, and improving user experience by reducing latency and preventing server crashes. In DevOps and cloud environments, load balancers are often integrated with auto-scaling groups to dynamically adjust resources based on demand.