CPU, GPU, TPU, NPU, DPU, QPU: Why Six Chips Exist Instead of One

Modern computing relies on six distinct processor types — CPU, GPU, TPU, NPU, DPU, and QPU — each optimized for a fundamentally different kind of workload. CPUs are generalist chips built to handle unpredictable, branchy code, while GPUs were originally designed for graphics rendering by running thousands of simple threads in parallel. Neural networks turned out to share the same mathematical structure as graphics workloads, making GPUs the accidental backbone of the AI industry. Google later developed the TPU specifically to accelerate tensor and matrix operations even more efficiently than GPUs. The core reason multiple chip types exist is that 'computation' is not a single uniform task — different workloads have radically different shapes that benefit from specialized hardware designs.