Reinforcement Learning · advanced · concept 125 of 176

🎮PPO (Proximal Policy Optimization)

For years the default RL algorithm, simpler and more stable than its predecessors, and the method used in the original RLHF pipelines. Newer group-relative variants have largely displaced it for language-model post-training, though PPO remains a standard baseline in robotics and control. Used in RLHF to fine-tune ChatGPT, in robotics, and in game AI. Balances exploration with stable training.