RegEx

-: 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