# MD5

> message-digest hashing algorithm

**Wikidata**: [Q185235](https://www.wikidata.org/wiki/Q185235)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/MD5)  
**Source**: https://4ort.xyz/entity/md5

## Summary
MD5 (Message-Digest Algorithm 5) is a message-digest hashing algorithm. It is classified as a cryptographic hash function, a special class of hash function designed with properties suitable for use in cryptography. MD5 was incepted in 1991 and is used for hashing.

## Key Facts
-   MD5 is an instance of a cryptographic hash function.
-   Its inception date is 1991.
-   It follows its predecessor, MD4.
-   MD5 is described by RFC 1321: The MD5 Message-Digest Algorithm.
-   It is known by multiple aliases, including MD5 Message-Digest Algorithm and Message Digest 5.
-   The algorithm's primary use is hashing.
-   It has a sitelink count of 49 across various platforms.

## FAQs
### Q: What is MD5?
A: MD5 is a message-digest hashing algorithm. It belongs to a special class of hash functions known as cryptographic hash functions, which are suitable for use in cryptography.

### Q: When was MD5 developed?
A: MD5 was incepted in 1991. It was developed as a successor to the MD4 algorithm.

### Q: What is MD5 used for?
A: MD5 is primarily used for hashing. As a cryptographic hash function, it is designed for applications in cryptography.

## Why It Matters
MD5 holds significance as an early and widely recognized message-digest hashing algorithm. As a cryptographic hash function, it was designed to possess properties suitable for use in cryptography, playing a role in verifying data integrity and ensuring authenticity in various digital contexts. Its inception in 1991 marked a step in the evolution of hashing algorithms, following its predecessor MD4. The algorithm's widespread adoption is reflected in its numerous aliases and references across various platforms. While its performance and security have been subjects of study, as indicated by sources like RFC 1810 and research on chosen-prefix collisions, its historical impact as a foundational cryptographic tool remains notable for its contribution to digital security practices.

## Notable For
-   Being a prominent message-digest hashing algorithm.
-   Its inception in 1991, following the MD4 algorithm.
-   Being formally described in RFC 1321: The MD5 Message-Digest Algorithm.
-   Its classification as a cryptographic hash function, suitable for use in cryptography.
-   Its widespread recognition, evidenced by a sitelink count of 49 and numerous aliases.

## Body

### Definition and Classification
MD5 is a message-digest hashing algorithm. It is an instance of a cryptographic hash function, which is a special class of hash function possessing properties suitable for use in cryptography.

### History and Development
MD5 was incepted in 1991. It was developed as a successor to the MD4 algorithm. Ron Rivest, an American cryptographer, mathematician, and computer scientist born on May 6, 1947, is related to the field of cryptographic hash functions.

### Use
The primary use of MD5 is hashing.

### Identification and References
MD5 is known by several aliases and identifiers:
-   **Aliases**: MD5 Message-Digest Algorithm, Message Digest Algorithm 5, Algoritmo MD5, RFC 1321, Message Digest 5, MD-5, Md5, Message-Digest 5, Md5sum, MD5 Hash.
-   **Described by Sources**:
    -   RFC 1321: The MD5 Message-Digest Algorithm
    -   RFC 1810: Report on MD5 Performance
    -   Chosen-prefix collisions for MD5 and applications
-   **Various Identifiers**:
    -   foldoc_id: MD5
    -   freebase_id: /m/04rh0
    -   quora_topic: MD5, 21232f297a57a5a743894a0e4a801fc3
    -   iptc_newscode: hashtype/MD5
    -   zhihu_topic_id: 19619705
    -   wikipedia_title: MD5
    -   niconicopedia_id: md5
    -   onix_codelist_id: 162/06
    -   stack_exchange_tag: https://stackoverflow.com/tags/md5
    -   rosetta_code_page_id: MD5
    -   store_id_google_play: MD5
    -   itu/iso/iec_object_id: 1.2.840.113549.2.5, 2.16.840.1.113719.1.2.8.50
    -   pronom_file_format_id: fmt/993
    -   file_format_wiki_page_id: MD5
    -   omegawiki_defined_meaning: 676314
    -   lc_and_marc_vocabularies_id: preservation/cryptographicHashFunctions/md5
    -   uniform_resource_identifier_scheme: md5
    -   computerlanguage.com_definition: MD5
    -   microsoft_academic_id_(discontinued): 157172786

### Related Entities
-   **Cryptographic hash function**: A special class of hash function that has certain properties which make it suitable for use in cryptography.
-   **Ron Rivest**: An American cryptographer, mathematician, and computer scientist, born on May 6, 1947.
-   **MD4**: The hashing algorithm that MD5 follows.

### Distinctions
MD5 is different from Maryland Route 5.

## References

1. Freebase Data Dumps. 2013
2. Quora
3. [UriSchemes/md5 - W3C Wiki](https://www.w3.org/wiki/UriSchemes/md5)
4. [OpenAlex](https://docs.openalex.org/download-snapshot/snapshot-data-format)