Windows Azure SQL Database server(A logical group of databases that acts as an authorization boundary and central administrative point for multiple databases. Each server includes logins similar to those in instances of SQL Server on your premises)
database server(A computer that is running Microsoft SQL Server and is used by an SMS/Configuration Manager site to store the site data; A DBMS (database management system) designed to be run in a client/server environment. These DBMS provide a stand-alone database engine that provides rich support for SQL and transactions. They are accessed through DBMS-based drivers. For example, Oracle, Informix, DB/2, or Microsoft SQL Server)
server database(выполняет обслуживание и управление базой данных и отвечает за целостность и сохранность данных, а также обеспечивает операции ввода-вывода при доступе клиента к данным Alex_Odeychuk); data backend(Alex_Odeychuk)