# Regular Expressions

## **Basic Special Characters**

* **/** - Regexes are enclosed within **forward slashes** to indicate where they begin and where they end
* **"^"** - The **circumflex accent** matches the beginning of the string or the beginning of the line. Your pattern will not match anything that has any text before if.
  * Example: `/^Once upon a time/` will match any line beginning with that sentence
* **$** - The **dollar sign** matches the end of the string. The opposite of the **^**
  * Example: `/ation$` will match any line ending with the string "ation"
* **\[]** - **Brackets** are used to match a single character from the list enclosed in them. Regexes accept ranges of letters such as **a-z** or **d-m**, and even ranges like **\[a-f0-6]** (a to f and zero to 6)
  * Example: `/[abc]/` will match either **a,b or c**
* **"\*"** - The asterisk acts as a quantifier to specify that the preceding character may appear 0 to n times.
  * Example: `/[ab]\*/` will match **abab, aaaaaaa** but will also match an empty string
* **+** - **Plus sign** is similar to `*`, but the preceding character has to appear at least once, it will match the same strings as the previous example, except for the empty string
* **{}** - The **braces** are used when you want to specify the number of times the preceding character should appear. Writing a single number within braces will match the strings that contain the preceding character or pattern that exact amount of times. Braces also include ranges. If you want a string that contains 4 to 8 characters use `{4,8}`