Regular Expression Cheat Sheet

The following are some of the most commonly used metacharacters and a very short description of their effect;

[ ] Match anything inside the square brackets for ONE character
^ (circumflex or caret) Matches only at the beginning of the target string (when not used inside square brackets (where it has a different meaning))
$ Matches only at the end of the target string
. (period or full-stop) Matches any single character
? Matches when the preceding character occurs 0 or 1 times only
* Matches when the preceding character occurs 0 or more times
+ Matches when the preceding character occurs 1 or more times
( ) Can be used to group parts of our search expression together
| (vertical bar or pipe) Allows us to find the left hand or right values