\ W characters matches
\ W matches non-character type character
\ D matches decimal digits
\ D matches non-decimal numeric characters
\ S matches a space character
\ S match than the other characters in non-space
Matches any one character
^ Beginning of the string
$ String end position
* 0 to multiple times 1-
? Zero or one
+ Matches one or more times
{N} object appears n times
{N,} object appears at least n times
{N, m} object appears at least n times m times the most frequent
