The PDB file format is mainly described in the PDB Contents Guide that was released by Brookhaven National Laboratory on December 20, 1996.
Any changes made to the PDB file format by the RCSB have been distributed to the PDB mailing list for discussion and review before they have been incorporated. These notices are archived at this site.
The RCSB has written several documents to accompany the PDB Contents Guide, including a Format FAQ to answer frequently asked questions about the PDB format, and a list of common format errors that have been submitted to the PDB.
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