Essential Coding Theory

Venkatesan Guruswami, Atri Rudra and Madhu Sudan

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The plan is to put up a draft of the whole book sometime in the future (eventually!).

Current Version

Below is a PDF of the book with the chapters that are now stable.

Draft of the book (August 26, 2025)

(No major changes since last version. Updated some bib section, corrected typos and added more exercises.)

Warning:There are some dangling/missing links.

Previous Versions

Listed below are previous versions of the book (in case you need an older version):

Oct 3, 2023.
- (Major changes from last version: Added chapter on applications of coding thoery in complexity theory; significantly revised the chapter on expander codes; re-arranged the chapters so that each part of the book is more tightly knit. )
January 31, 2022.
- (Major changes from last version: Added chapters on expander codes, linear time encodable codes, locally recoverable codes and complexity of coding problems.)
March 15, 2019.
- (Major changes from last version: Added chapter on decoding RM code and an appendix on algebraic algorithms)
December 18, 2018.
July 27, 2018.
Old version of the webpage that has separate chapter files.

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.

Acknowledgment

The material in this webpage is supported in part by the National Science Foundation under CAREER grant CCF-0844796. Any opinions, findings and conclusions or recomendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation (NSF).