The Bird Contacts API allows you to manage a directory of contact information for all your customers. A single contact record should be created for each customer, and each record can contain each of multiple forms of contact information for that customer. Each unique bit of contact information (e.g. phone and email) is called an Identifier. You can also define a custom schema of contact attributes that can then be used to store additional information about your customers. Contact records can be used with the Channels and Conversations APIs.