'0:0:5' And ('nndn'='nndn | {keyword}') Waitfor Delay

: Attempts to close the existing SQL query's syntax (like a string literal and parenthesis).

: If you do not have explicit permission to test this site, stop immediately. Unauthorized security testing can be illegal. {KEYWORD}') WAITFOR DELAY '0:0:5' AND ('nNDN'='nNDN

It looks like you are testing for a vulnerability, specifically a time-based blind SQL injection . : Attempts to close the existing SQL query's