You really should do the reading the others suggested, and CGI.pm and taint mode are a good idea too.

How embarassed will you be if your script allows someone to crack the machine and use it as a kidporn or war3z trading server?

Anyhow, just so you can fix your current "URGTENT" urgent problem (and right after that, read the links provided by the good monks). 

$variable =~ s/_/ /g;

[download]
translated, that's "variable becomes substitute /(underscore)/ with /(space)/ globally

In reply to Re: URGTENT: Need to remove undescore characters by u914
in thread Replacing underscore characters with whitespace by markinoz

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