Robert Kline has created a helpful side-by-side comparison of Perl and PHP.

[url]http://www.cs.wcupa.edu/~rkline/perl2php/[/url]

Example:
Code:
%ENV
 
$ENV{REQUEST_METHOD}
 
$ARGV[$i]
 
$0
PHP Code:
$_SERVER
 
$_SERVER[REQUEST_METHOD]
 
$argv[$i+1]
 
$argv[0]  # Php/CGI only