# Load Balancing
Confidence: high
Last verified: 2026-05-22
Generation: human_only


## TL;DR

A load balancer distributes incoming traffic across multiple backend servers, improving scalability, reliability (failover), and performance. Types: Layer 4 (TCP, fast, no content inspection), Layer 7 (HTTP, content-based routing, SSL termination).

## Core Explanation

Algorithms: round-robin, least connections, IP hash (session persistence), weighted (unequal server capacity). Health checks probe backend availability. NGINX and HAProxy are the most popular software load balancers. Cloud-native: AWS ALB/NLB, GCP Cloud Load Balancing. Global server load balancing (GSLB) routes traffic across regions via DNS.

## Further Reading

- [NGINX Documentation](https://nginx.org/en/docs/)