| . | Any character except new line (\n) |
| (a|b) | a or b |
| (…) | Group |
| (?:…) | Passive (non-capturing) group |
| [abc] | Range (a or b or c) |
| [^abc] | Not (a or b or c) |
| [a-q] | Lower case letter from a to q |
| [A-Q] | Upper case letter from A to Q |
| [0-7] | Digit from 0 to 7 |
| \x | Group/subpattern number “x” |
Ranges are inclusive.