PHP Manual: Inserts HTML line breaks before all newlines in a string

string nl2br(string $string, bool $use_xhtml = true)

Returns string with <br /> or <br> inserted before all newlines (\r\n, \n\r, \n and \r).

Returns the altered string.

Example #1 Using nl2br

<?php
echo nl2br("foo isn't\n bar");
?>

The above example will output:

foo isn't<br />
 bar

Example #2 Generating valid HTML markup using the use_xhtml parameter

<?php
echo nl2br("Welcome\r\nThis is my HTML document", false);
?>

The above example will output:

Welcome<br>
This is my HTML document

Example #3 Various newline separators

<?php
$string = "This\r\nis\n\ra\nstring\r";
echo nl2br($string);
?>

The above example will output:

This<br />
is<br />
a<br />
string<br />

nl2br