A recipient is someone who receives email alerts from contracts, documents, or requirements. All users are potential recipients, but not all recipients are users. If you send an alert to someone who is not a user, that person will receive an email but will not have access to Lextree.
Users may create recipient records when setting up email alerts for contracts and related records. Admin users may review and update alert recipient name and email information at "Settings" > "Users & Groups" > "Recipients".