The Little Book of Reinforcement Learning
Summary
A concise introduction to Reinforcement Learning, from basics to applied algorithms, with PyTorch implementations and supplementary proofs.
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alxndrTL/little-book-rl
Source: https://github.com/alxndrTL/little-book-rl
The Little Book of Reinforcement Learning
This is the associated GitHub page of the Little Book of Reinforcement Learning.
This book is a short introduction to Reinforcement Learning, from the basics to applied algorithms.

In this repo, along with the book itself, you can find the supplementary material of the book. More precisely:
- under the
algos/folder, the Pytorch-based implementation of the different algorihms covered in the book, from MC to PPO. - under the
supplementary/folder, you can find detailed explanations and rigorous proofs for the dynamic programming algorithms briefly covered in the book. This is a document I wrote in 2021.
More material is subject to be added along the way in this repo.
You can print one for youself here.
Versions of the book :
- V1 (June 2026)
The book is distributed under a non-commercial Creative Commons license (CC BY-SA 4.0).
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