A plural is a special type of attribute that can contain any number of child attributes and child values. For example, the profile plural, which tracks the different social login identity providers a user has employed, can contain multiple entries (for Facebook, for Twitter, for LinkedIn, for ….), with each of those entries made up of multiple attributes (id, accessCredentials, domain, etc.).
Because a plural attribute is primarily a container for other attributes, no data validations or transformations are set on the plural itself. Instead, validations and transformations are set on the individual attributes stored in the plural. For example, the domain attribute is a string attribute; by default, both the Required and the Case Sensitive validations are enabled on this child attribute: