Difference between CRC and hash method (MD5, SHA1)

Question

Both CRC and hash methods can be used to verify the integrity of the original data. Why do most systems uses hash method nowadays?

Answer 1

HASH methods (ONE WAY ENCRYPTION) are more complex (and powerful) than simple check codes (CRC). Not only they could be used to verify data integrity, but they also make sure no one could infer the original message that originated the hash value.