The @@IDENTITY, SCOPE IDENTITY(), and IDENT_CURRENT functions all return the Identity value (ID value) of the recently (latest) inserted record, however, there is a distinction
Tag: @@IDENTITY in SQL Server
IDENTITY usage in SELECT INTO – SQL Server
The IDENTITY function can be defined for an identity column when the table is created and for a new column when the table is altered.
SQL Server Identity Functions
Identity values are handled by a number of functions in Microsoft SQL Server. The functions assist in establishing the automatic sequential value for table rows,
Big Data & SQL 