Perl allows you to easily concatenate two strings using the . and .= operators. While you can quickly outgrow it, it is often enough. You can also interpolate string values inside some types of string constants. Therefore, you can say:

my $name = "Sophie";
my $city = "London";
my $large_string = "Hello $name, welcome to $city!";
# $large_string is now "Hello Sophie, welcome to London!"

You can also interpolate array elements and hash keys:

my @colors = ("Red", "Orange", "Yellow", "Green", "Indigo", "Blue", "Violet");
my %capitals = (
    "France" => "Paris",
    "Germany" => "Berlin",
    "Spain" => "Madrid",
    "Japan" => "Tokyo",
);

print "Japan has a flag with a $colors[0] circle, and a its capital is $capitals{Japan}\n";

Furthermore, one can interpolate more complex expressions using the turtle operator - @{[]}, although if you're resorting to doing it, you should probably use the more advanced techniques below:

#!/usr/bin/perl

use strict;
use warnings;

print "Please enter a number:\n";
my $n = <>;
chomp($n);

my $string = "$n is @{[($n % 2 == 0) ? 'even' : 'odd' ]}";

print "$string\n";

Perl also gives you a large selection of delimiters for strings as well as here-documents, which allow assigning multiple-line string constants with a user-specified terminating delimiter.

Nevertheless, please read on to see what other and often better options exist.

sprintf() is a built-in Perl function for formatting its arguments, similar to the sprintf function provided by C and other programming languages. Make sure you familiarize yourself with it.

my $formatter =
    Text::Sprintf::Named->new(
        {fmt => "Hello %(name)s! Today is %(day)s!"}
    );

# Returns "Hello Ayeleth! Today is Sunday!"
$formatter->format({args => {'name' => "Ayeleth", 'day' => "Sunday"}});

Template Toolkit is a sophisticated and powerful templating system for Perl, with many extensions on the CPAN. Also see a presentation that Shlomi Fish gave about Template Toolkit, that explains why one should use a template system and especially Template Toolkit.

A Perl module for preparing reports as text and some other higher-level formats.

A module for formatting fixed-width text. You should use it instead of the built-in perlform facility assuming you want something like that.

A CPAN module for outputting text tables.

A convenient CPAN module for outputting XML.