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hash is good enough in most scenarios.

hash generally generates numbers from keys or strings.

types of hash

There are several types of hash functions used in computer science and cryptography. Here are some of the main categories and examples:

Cryptographic Hash Functions

These are designed to be secure and resistant to attacks:

SHA (Secure Hash Algorithm) Family

  • SHA-1 (160 bits, now considered insecure)
  • SHA-2 (includes SHA-256 and SHA-512)
  • SHA-3 (newest member of the SHA family)[1]

MD (Message Digest) Family

  • MD5 (128 bits, no longer considered secure for cryptographic purposes)[1]

Other Cryptographic Hashes

  • RIPEMD-160 (160 bits, considered secure)
  • Whirlpool (512 bits, based on AES encryption)[4]

Non-Cryptographic Hash Functions

These are designed for speed and efficiency in general-purpose computing:

Checksums and Cyclic Redundancy Checks (CRCs)

Used for error detection:

  • CRC-32
  • Adler-32
  • Fletcher's checksum[3]

Special-Purpose Hash Functions

  • Perceptual hashing (pHash) - for finding similar multimedia files
  • Locality-sensitive hashing - for finding similar items in large datasets[3]

Hash Function Methods

These are techniques used to create hash functions:

  • Division Method
  • Multiplication Method
  • Mid-Square Method
  • Folding Method[5]

When choosing a hash function, consider factors like security requirements, speed, and the specific use case. For cryptographic purposes, SHA-256 or SHA-3 are generally recommended. For non-cryptographic uses like hash tables, faster algorithms like MurmurHash or xxHash may be more appropriate[1][4].

Citations: [1] https://www.scholarhat.com/tutorial/datastructures/hashing-in-data-structures [2] https://www.sciencedirect.com/topics/computer-science/hashing-algorithm [3] https://en.wikipedia.org/wiki/List_of_hash_functions [4] https://www.okta.com/identity-101/hashing-algorithms/ [5] https://www.geeksforgeeks.org/hash-functions-and-list-types-of-hash-functions/ [6] https://www.appsealing.com/hashing-algorithms/ [7] https://www.2brightsparks.com/resources/articles/introduction-to-hashing-and-its-uses.html [8] https://www.ibm.com/docs/en/i/7.4?topic=sf-hash-md5-hash-sha1-hash-sha256-hash-sha512

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