OUT is not a command. It is a name of filehandle. First of all you should open file. Once you have created file you get a filehandle which allows you to do various operations with file. See perldoc open.

open(OUT, "> dataform.html") or die "Can't open file: $!";
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This code opens 'dataform.html' for write and assigns filehandle to OUT.

Once file is opened you can write into it using filehandle OUT. You can use print to do it but you should pass it filehandle.

print OUT "Whatever you want";
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Note that there is no comma between OUT and message you are writting into the file.

Once you have finished writting the file you should close filehandle.

close OUT;
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