http://www.perlmonks.org?node_id=11112226


in reply to program cant find values that start with $

Your original code gives the user the full power of regular expressions. When he intends a literal dollar sign, he has to escape it himself. The \Q...\E solution restricts him to literal character searches. From a security viewpoint, this restriction is a huge benefit. Casual users will not mind the restriction, in fact most will appreciate the convenience it provides.
Bill