Given raw logits z, softmax(z/T) is the next-token probability distribution. T=1 is the model's learned distribution. T<1 sharpens it (more deterministic). T>1 flattens it (more diverse). T=0 is pure greedy (always the argmax).
Low T for code, factual answers. High T for creative writing. Beyond ~1.5, outputs become incoherent for most models.