How LLMs Are Trained After Pretraining: SFT, Reward Models, and RL Without the Alphabet Soup

A practical map of LLM post-training: how SFT, reward models, RL (PPO, GRPO), DPO, and RLVR fit together, and why a reward model is not RL.

Source: [HackerNoon](https://hackernoon.com/how-llms-are-trained-after-pretraining-sft-reward-models-and-rl-without-the-alphabet-soup?source=rss)