Difference between the SHA and SHA-1 message digests

SHA stands for Secure Hash Algorithm. SHA-1 is more secure than SHA.

From the standard:

“SHA-1 is a technical revision of SHA (FIPS 180). A circular left shift operation has been added to the specifications in section 7, line b, page 9 of FIPS 180 and its equivalent in section 8, line c, page 10 of FIPS 180″