URN stands for Uniform Resource Name, a standardized identifier for a communications channel - such as a phone number or Twitter ID - that is associated with a contact. 

Consider a flow that is running through a webchat. If you wanted to follow-up with that contact in a day or two by text message, you might need to get their phone number. In the example below, we ask for the contact’s phone number and add it as a URN to the contact’s information using the variable @results.phone.value

For more information on how to use flow variables, check out Introduction to Flow Variables.

On our platform, there are a variety of URNs that you can add to a contact, including phone number, Twitter ID, email address, and webchat ID. To see the full list of URNs, click the down arrow. 

Up Next: Add the Contact to a Group / Remove the Contact from a Group