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

Regular expressions can be extremely useful whenever you need to make the computer do something with text. For example, when you need to check that what user typed is a real email, or automatically replace every uppercase letter F into a lowercase letter F. But as useful as they are, regular expressions can be extremely confusing and intimidating for beginners. In this podcast I’m going to explain regular expressions in a simple and accessible way, and help you start using them in your day-to-day work.