Topic
RLHF, DPO & Instruction Tuning
7 posts on rlhf, dpo & instruction tuning — part of glossary on the n4n AI blog.
What is RLHF? Reinforcement learning from human feedback
A technical explainer of RLHF — how reward modeling, PPO, and human preference data align LLMs to follow instructions and avoid harmful outputs.
What is instruction tuning? A practical explanation
A practical guide to instruction tuning — what it is, how it differs from pretraining and RLHF, and why it matters for building usable LLMs.
What is DPO? Direct preference optimization explained
Direct Preference Optimization (DPO) explained for engineers — how it works, why it replaces PPO in RLHF, a concrete training example, and common misconceptions.
RLHF vs DPO: how the two alignment methods differ
A practical comparison of RLHF and DPO alignment methods covering training dynamics, compute costs, implementation complexity, and when to use each approach.
How RLHF trains a reward model
A step-by-step guide to training a reward model for RLHF, from preference data preparation through validation and deployment for PPO.
How ChatGPT was trained with RLHF
A technical breakdown of ChatGPT's RLHF pipeline — supervised fine-tuning, reward modeling, and PPO — with code sketches and honest tradeoffs.
Constitutional AI vs RLHF: how Claude is aligned
Technical comparison of Constitutional AI and RLHF alignment methods, covering training pipelines, trade-offs, and when to use each approach.
More topics in glossary
- Structured Outputs & JSON Mode19
- AI Agents Fundamentals12
- Hallucination in LLMs11
- Sampling Parameters: Top-p, Top-k & Penalties11
- Context Window & Context Length10
- Fine-Tuning Fundamentals9
- Foundation Models: Base vs Instruct vs Chat9
- Model Families & Naming Conventions: GPT-5, Claude, Gemini 3, Llama 4, Mistral, DeepSeek, Qwen, Grok9
- Grounding & Fact-Checking in AI8
- LLM Benchmarks: MMLU, HumanEval, SWE-bench & GPQA8
- Max Tokens, Stop Sequences & Output Truncation8
- Quantization Formats: GGUF, GPTQ, AWQ & INT4/INT88