# Maildir

> e-mail format

**Wikidata**: [Q1246497](https://www.wikidata.org/wiki/Q1246497)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Maildir)  
**Source**: https://4ort.xyz/entity/maildir

## Summary
Maildir is an e-mail format developed by Daniel J. Bernstein in 2000. It is designed as a file format and data format for storing email messages in a directory structure.

## Key Facts
- Maildir was developed by Daniel J. Bernstein, an American-German mathematician, cryptologist, and programmer
- The format was created in 2000, with documentation first archived on September 2, 2000
- Maildir is classified as both a software component and a file format
- The format has documentation available at http://cr.yp.to/proto/maildir.html
- Maildir has 11 sitelinks across various language versions of Wikipedia
- The format is supported in multiple languages including Czech, German, English, Spanish, French, Japanese, Dutch, Polish, Russian, and Swedish
- Maildir has a Freebase ID of /m/0gbvx

## FAQs
### Q: What is Maildir?
A: Maildir is an e-mail format that stores messages in a directory structure with three subdirectories (new, cur, tmp) rather than in a single file. This design allows for concurrent access without file locking.

### Q: Who created Maildir?
A: Maildir was created by Daniel J. Bernstein, an American-German mathematician, cryptologist, and programmer known for his work in cryptography and software development.

### Q: When was Maildir developed?
A: Maildir was developed in 2000, with its initial documentation archived on September 2, 2000, as evidenced by web archive records.

### Q: What problem does Maildir solve?
A: Maildir solves the problem of concurrent access to email messages by using a directory structure instead of a single file, eliminating the need for file locking mechanisms that can cause performance issues.

## Why It Matters
Maildir represents a significant advancement in email storage architecture by addressing the limitations of traditional single-file mailbox formats. Its directory-based approach allows multiple processes to safely read and write emails simultaneously without the need for file locking, which was a common bottleneck in earlier systems. This design has made Maildir particularly valuable in high-traffic email servers and environments where reliability and performance are critical. The format's simplicity and effectiveness have contributed to its widespread adoption in various email systems and servers, demonstrating how thoughtful architectural design can solve fundamental problems in data management.

## Notable For
- Directory-based storage structure that eliminates the need for file locking
- Concurrent access support allowing multiple processes to safely interact with email messages
- Simple yet robust design that has stood the test of time since its introduction in 2000
- Cross-platform compatibility and language support across multiple programming environments
- Creation by Daniel J. Bernstein, a respected figure in mathematics and cryptography

## Body
### Development
Maildir was created by Daniel J. Bernstein in 2000. The format was first documented and made available through Bernstein's personal website at cr.yp.to. The initial documentation has been preserved in web archives, with the earliest archived version dating back to September 2, 2000.

### Technical Classification
Maildir is classified as multiple types of digital formats:
- Software (as a non-tangible executable component)
- File format
- Data format

This dual classification reflects both its implementation as a software solution and its role as a standardized method for organizing email data.

### Documentation and Availability
The primary documentation for Maildir is available at http://cr.yp.to/proto/maildir.html. This resource has been preserved and remains accessible to developers implementing the format. The format has been recognized in various knowledge bases, including Freebase with the ID /m/0gbvx.

### International Reach
Maildir has achieved international recognition with Wikipedia articles available in 10 languages: Czech (cs), German (de), English (en), Spanish (es), French (fr), Japanese (ja), Dutch (nl), Polish (pl), Russian (ru), and Swedish (sv). This multilingual presence indicates its adoption and relevance across different linguistic and regional computing communities.

## References

1. [Source](https://web.archive.org/web/20000902121438/http://cr.yp.to:80/proto/maildir.html)
2. Freebase Data Dumps. 2013