Special Characters

Some characters have special meaning in regex. These are called metacharacters.

The Metacharacters

These characters are special in regex:

. ^ $ * + ? { } [ ] \ | ( )

To match them literally, you must escape them with a backslash \.

The Dot (.)

The dot matches any single character (except newline).

Notice c.t matches cat, cot, cut, c@t, c1t - but NOT cart (two characters between c and t).

Escaping Special Characters

To match a literal dot, use \.

Common Escapes

File Extensions

A practical example - matching file extensions:

Practice Playground

Try matching:

• $19.99 - escape $ and .
• @example - @ is not special
• (a*b) - escape parentheses and asterisk

Escape Reference

Character	Escaped	Matches
.	\.	Literal period
$	\$	Literal dollar sign
?	\?	Literal question mark
*	\*	Literal asterisk
+	\+	Literal plus sign
(	\(	Literal parenthesis
[	\[	Literal bracket
\	\\	Literal backslash

Key Takeaways

• The dot . matches any single character
• Metacharacters have special meaning
• Use backslash \ to escape special characters
• When in doubt, escape it!