Load balancing is the practice of spreading incoming work across several servers so that no single one is overloaded and the system as a whole stays fast and available. When traffic grows beyond what one machine can comfortably handle, you add more servers and share the load between them. The tool that carries this out is a load balancer.
Think of a busy ticket office with one window and a long queue. Open three more windows and split the crowd between them, and everyone is served far quicker. Load balancing does exactly this for digital traffic, and it brings a second benefit: if one window closes, the others absorb the line, so service never stops entirely. That resilience is why it pairs so well with auto-scaling, which opens new windows automatically when the queue grows.
There are different ways to share the load. Round robin sends requests to each server in turn, while least connections favours whichever server is least busy. The right choice depends on how even or uneven your workloads are.
It is worth knowing what load balancing does not solve on its own. If your database behind those servers is the real bottleneck, adding web servers just moves the queue. And a failed server only stays out of the way if uptime monitoring and health checks are actually watching, otherwise traffic keeps flowing to a machine that is already down. So good load balancing starts with measuring where the real pressure sits, not with blindly adding servers.
At TopDevs we design load balancing into systems that need to stay up under pressure, so a traffic spike or a failed server never takes a client’s service offline.
