Regular expressions are very useful if you want to limit the values stored in a field in the way that only some specific information can be added. Like if you have an “Integer” attribute then only numbers can be stored, or an “Email” attribute can only store a proper email address account.

There are some “Regexes” already defined in the system, but you can create new ones. Click on “Add new value” and “Create New Regex” screen will be displayed, just type the “Name” of your regex, the “Value”, check the option “Is hidden” if needed and save your new regex.