Tensor core (matrix core)
Beginner
A special unit in a GPU core that multiplies whole small blocks of numbers in one go, instead of one pair at a time.
Novice
A hardware unit that performs a small matrix multiply-and-add (for example 4×4 or larger tiles) as a single instruction. NVIDIA calls them tensor cores, AMD matrix cores. They now provide most of a GPU’s AI math.
Expert
A small systolic-style MMA datapath fed from registers (and, from Hopper on, directly from shared memory). One instruction does tens to hundreds of FMAs, amortizing fetch, decode and register-read energy. Supports low-precision inputs with wider accumulation.
Explained in SIMT and GPUs (Architectures).
See also: MAC (multiply-accumulate), systolic array.