MD5 or SHA1 Encription

Which is best? I know MD5 is 128-Bit and SHA1 160-Bit. But which one is better for a login system!

http://www.google.com/search?q=md5+vs+sha1

Whichever hash method you use, always append/prepend a "salt" string to the value being hashed. This will make the brute-force/dictionary/database-lookup methods ineffective at finding the original value.

MD5 already has a lookup table constructed for unsalted values that will provide an enterable value to match any hash and so must use a salt to have any security at all. SHA1 is way more secure and has yet to be broken that way. With a salt MD5 is secure enough for most purposes.

sha indeed

sha1 all the way

i use sha1()