What are the differences between MD5, SHA and RSA?

To answer the interview question "What are the differences between MD5, SHA, and RSA?" comprehensively, it's important to understand that MD5 and SHA are cryptographic hash functions, while RSA is an asymmetric encryption algorithm. Here are the key differences:

MD5 (Message Digest Algorithm 5)

• Type: Cryptographic hash function.
• Output: Produces a 128-bit hash value.
• Speed: Generally faster than SHA algorithms.
• Security: Considered insecure due to vulnerabilities that allow for collision attacks, where two different inputs produce the same hash value[12][13][17].
• Use Cases: Historically used for checksums and data integrity verification, but not recommended for cryptographic security due to its weaknesses[13][17].

SHA (Secure Hash Algorithm)

• Type: Family of cryptographic hash functions.
• Variants: Includes SHA-0, SHA-1, SHA-2 (SHA-224, SHA-256, SHA-384, SHA-512), and SHA-3.
• Output: Varies by variant; for example, SHA-1 produces a 160-bit hash, while SHA-256 produces a 256-bit hash[12][13][19].
• Speed: Slower than MD5 but offers better security. SHA-256 is a good balance between security and performance[17][19].
• Security: SHA-1 is deprecated due to vulnerabilities, while SHA-2 and SHA-3 are currently considered secure[12][13][19].
• Use Cases: Widely used in digital signatures, certificates, and data integrity checks. SHA-256 is commonly used in blockchain technology[1][2][3].

RSA (Rivest-Shamir-Adleman)

• Type: Asymmetric encryption algorithm.
• Keys: Uses a pair of keys – a public key for encryption and a private key for decryption[8][9][10].
• Security: Based on the mathematical difficulty of factoring large prime numbers. The security of RSA depends on the key size; commonly used key sizes are 2048 bits and 3072 bits for higher security[8][10].
• Use Cases: Used for secure data transmission, digital signatures, and key exchange. It is a fundamental component in many security protocols like SSL/TLS, SSH, and PGP[9][10].
• Performance: Slower than symmetric encryption algorithms a...