Quick reference
.Any character except newline
\dDigit (0–9)
\wWord character (a–z, A–Z, 0–9, _)
\sWhitespace (space, tab, newline)
\bWord boundary
^Start of string (or line with m)
$End of string (or line with m)
*0 or more
+1 or more
?0 or 1 (or lazy quantifier)
{n,m}Between n and m times
[abc]Character class
[^abc]Negated character class
(abc)Capture group
(?:abc)Non-capturing group
a|bAlternation (a or b)