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Nice. For those wondering what Reed-Solomon codes are all about: they are extra data that allows certain types of corruption to be detected and fixed.

I believe RS codes are used on optical media such as CDs and DVDs which allows perfect playback with a few scratches here and there. They're also used in QR codes, so even if the scan is imperfect, the data can be reconstructed correctly. In the case of QR codes, the standard allows the QR code creator to set the level of error correction, providing a wide range of of data size vs resilience to corruption choices.

Exactly. Thanks for adding that. They're also used in nearly all large storage systems from Amazon S3 to RAID6.
And also for Forward Error Correction (FEC) on Optical Transport Networks.
Reed-Solomon is also used in parity files (Parchive [1]) which were especially popular in the newsgroup/usenet days.

> parity files could be created that were then uploaded along with the original data files. If any of the data files were damaged or lost while being propagated between Usenet servers, users could download parity files and use them to reconstruct the damaged or missing files.

[1]: https://en.wikipedia.org/wiki/Parchive