A sequence of letters and numbers
Definition: A string is a sequence of letters and numbers used in PHP programming. A string is not a number, and has no numeric value to the program, although it can contain numbers. A string can be represented by a variable. It can contain letters, numbers and symbols. A string in PHP might look like this:
<?php
$string1 = "This is a string";
?>
<?php
$string1 = "This is a string";
?>
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