Symbols Regular Expressions

^     |Anchor for the beginning of a line
$     |Anchor for the end of a line
\A    |Anchor for the start of a string
\Z    |Anchor for the end of a string
.     |Any character
\w    |Any letter, digit, or underscore
\W    |Anything that \w doesn't match
\d    |any digit
\D    |anything that \d doesn't match- non digits
\s    |Whitespace such as spaces, tabes, newlines, and so on
\S    |non whitespace - any visible character

Character and sub-expression modifiers
*     |Match zero or more occurrences of the preceding character, and match as many as possible
+     |Match one or more occurrences of the preceding character, and match as many as possible
*?    |Match zero or more occurrences of the preceding character, and match as few as possible
+?    |Match one or more occurrences of the preceding character, and match as few as possible
?     |Match either one or none of the preceding character
{x}   |Match x occurrences of the preceding character
{x,y} |Match at least x occurrences and at most y occurrences