The backslash (\) has special meaning in JavaScript regular expressions. It’s used before certain characters as a way to provide a special meaning. For example, the /t/ as a regular expression matches itself literally. If it is preceded by the backslash character in the regular expression, such as /\t/, the regular expression would match a tab.
The general regular expression backslash usages are listed below:
\t = tab
\n = newline
\f = form feed
\r = carriage return
\w = any ASCII word character
\W = any character that is not an ASCII word character
\d = any ASCII digit
\D = any character that is not an ASCII digit
\s = any whitespace character
\S = any character that is not a whitespace character
The backslash character can also be used in front of characters that are used specially in regular expressions as a way to match those characters literally. For example, the dollar sign ($) is used in regular expressions to specify the end of a pattern. To match it literally, precede it with a backslash, such as /\$/.
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JavaScript Regular Expressions
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