C:\Old_Data\perlp>perl t33.pl
david
        Website: www.facebook.com, Category: Social Networking
john
        Website: www.yahoo.com, Category: Entertainment
        Website: www.yahoo.com, Category: Entertainment
        Website: www.yahoo.com, Category: Entertainment
        Website: www.facebook.com, Category: Social Networking
mike
        Website: www.google.com, Category: Search Engines


Name: john
        Website Count
        www.yahoo.com       3
        www.facebook.com    1

        Type Count
        Entertainment       3
        Social Networking   1


Name: mike
        Website Count
        www.google.com      1

        Type Count
        Search Engines      1


Name: david
        Website Count
        www.facebook.com    1

        Type Count
        Social Networking   1
[download]

user="john" website="www.yahoo.com" type="Entertainment"
user="john" website="www.yahoo.com" type="Entertainment"
user="john" website="www.yahoo.com" type="Entertainment"
user="david" website="www.facebook.com" type="Social Networking"
user="john" website="www.facebook.com" type="Social Networking"
user="mike" website="www.google.com" type="Search Engines"
[download]

In my program I use 2 hashes - one to count the number of sites visited by each user, %count, and one to count each address and category (by user), %data. It seems to work OK for this small data set.

#!/usr/bin/perl
use strict;
use warnings;

my (%data, %count);

while (<DATA>) {
    my ($user, $site, $cat) = /"([^"]+)"/g;
    $data{$user}{ qq{$site$;$cat} }++;
    $count{$user}++;
}

for my $user (sort keys %data) {
    my $href = $data{$user};
    print $user, "\n";
    for my $key (keys %$href) {
        my $str = sprintf "\tWebsite: %s, Category: %s\n", split /$;/,
+ $key;
        print $str x $href->{$key};
    }
}

my @ordered = sort {$count{$b} <=> $count{$a}} keys %count;

print "\n\n";

for my $user (@ordered) {
    my $href = $data{$user};
    print "Name: $user\n\tWebsite Count\n";
    for my $key (sort {$href->{$b} <=> $href->{$a}} keys %$href) {
        printf "\t%-20s%d\n", (split /$;/, $key)[0], $href->{$key};
    }
    print "\n";
    print "\tType Count\n";
    for my $key (sort {$href->{$b} <=> $href->{$a}} keys %$href) {
        printf "\t%-20s%d\n", (split /$;/, $key)[1], $href->{$key};
    }
    print "\n\n";
}
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Here is a dump of %data.

$VAR1 = {
          'john' => {
                      'www.yahoo.com‡˜Entertainment' => 3,
                      'www.facebook.com‡˜Social Networking' => 1
                    },
          'mike' => {
                      'www.google.com‡˜Search Engines' => 1
                    },
          'david' => {
                       'www.facebook.com‡˜Social Networking' =>
                     }
        };
[download]