Regular expressions

Character     Description

^         Matches the beginning of input
$         Matches the end of input
|          A logical “or” statement
.          Matches a single character
+         Matches the character to the left 1 or more times
*         Matches the character to the left 0 or more times
?          Matches the character the the left o or 1 times
\          Removes special meanings
( )        Affects order of operations
[ ]        Creates a group of characters