Regular expressions are a language of their own. When you learn a new programming language, they're this little sub-language that makes no sense at first glance. Below are eight regular expressions that you should know for your next coding project.

Username

Pattern:/^[a-z0-9_-]{3,16}$/

Password

Pattern:/^[a-z0-9_-]{6,18}$/

Hex Value

Pattern:/^#?([a-f0-9]{6}|[a-f0-9]{3})$/

Slug

Pattern:/^[a-z0-9-]+$/

Email

Pattern:/^([a-z0-9_\.-]+)@([\da-z\.-]+)\.([a-z\.]{2,6})$/

URL

Pattern:/^(https?:\/\/)?([\da-z\.-]+)\.([a-z\.]{2,6})([\/\w \.-]*)*\/?$/

IP Address

Pattern:/^(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$/

HTML Tag

Pattern:/^<([a-z]+)([^<]+)*(?:>(.*)<\/\1>|\s+\/>)$/