-: Capture Data :-
(…)
-: Group but not capture :-
(?:…)
-: Optional Data :-
[...]?
(…)?
([...])?
-: Negate class :-
[^...]
-: Positive Look Ahead :-
(?=…) – look forward from left to right
-: Negative Look ahead :-
(?!…) –
-: Positive Look Behind :-
(?<=…) – look backward from right to left
-: Negative Look Behind :-
(?<!…) –
-: Single-Line Mode :-
allow the dot (.) not to match newline