Metacharacter

A metacharacter is a character, or a sequence of characters, with a special meaning in a computing application. It might be used to represent another set of characters, an unprintable character, or a logical operation. For example, in some applications, \n is interpreted as a newline. (In this case, a backslash is used to escape the n character, indicating that it should be interpreted as a metacharacter.)

Metacharacters are frequently used in regular expressions. For instance, the following Perl statement uses a regular expression to delete any newlines from the contents of the variable $data.

$data =~ s/\n//;

This statement says "assign a new value to $data which substitutes any newline in $data with nothing."

For a list of common metacharacters, and examples of how to use them, please see our regular expressions quick reference.

Character, Escape, Escape character, Metadata, Programming terms, Regular expression, Wildcard