1. A character that is used to carry a special meaning, such as a caret (^, beginning of line), a dollar sign ($, end of line), or an asterisk (*, match any character). To use one of these characters without special meaning, you must either precede it with a backslash (\) or enclose it within quotation marks. Bypassing the special meaning of a metacharacter is called escaping or quoting the character. From Linux Guide @FirstLinux