Hashing transforms data into a fixed-size string of characters. It is used for data integrity, password storage and efficient data retrieval.
Key Features:
- Produces fixed-length output
- Is deterministic (same input always produces same output)
- Is one-way (cannot reverse hash to original data)
- Aims for uniform distribution of hash values
- Detects changes in input data
Common Hashing Algorithms:
- MD5 (not secure for cryptographic use)
- SHA-256
- bcrypt
- Argon2
Uses of Hashing:
- Efficient data lookup in hash tables
- Password storage in databases
- File integrity checks
- Digital signatures
- Data deduplication
Cryptographic hash functions have additional security properties to resist attacks. They are crucial for many cybersecurity applications.