So if md5( ) generates the most secure hash, why would you ever use the less secure crc32( ) and sha1( )?

Correct Answer: Crypto usage in PHP is simple, but that doesn’t mean it’s free First off, depending on the data that you’re encrypting, you might have reasons to store a 32-bit value in the database instead of the 160-bit value to save on space Second, the more secure the crypto is, the longer is the computation time to deliver the hash value A high volume site might be significantly slowed down, if frequent md5() generation is required