What makes llama.cpp different?
llama.cpp is an inference engine: it loads a model and runs it so you can send a prompt and get tokens back. What sets it apart is restraint. It is written in C++ with few dependencies, and it reads models in the GGUF file format, a single file that holds the weights and the metadata needed to run them. That combination means it starts on hardware that heavier servers will not touch: a laptop processor, a small graphics processor (GPU), or a big one if you have it.
GGUF files usually carry quantized weights, stored in a smaller number format to shrink the model, which is what lets a large model fit on a small machine at the cost of some precision. llama.cpp was built around that idea, so running a quantized model is the normal path, not a workaround.
Where does it sit against the bigger servers?
The heavier serving engines are built to keep a large GPU busy serving many callers at once. llama.cpp aims somewhere else: get a model running on the hardware you already have, with as little ceremony as possible. That is also why several friendlier local-model runners are built on top of it. They add a nicer interface and model management, and llama.cpp does the actual running underneath. If you want raw throughput from a large accelerator, reach for a server built for that. If you want a model running tonight on modest hardware, this is often the shortest path.