different types of Session state management options available with ASP.NET?

1)In-Process
2) Out-of-Process state management.

In-Process stores the session in memory on the web server. This requires the a "sticky-server" (or no load-balancing) so that the user is always reconnected to the same web server.

Out-of-Process Session state management stores data in an external data source. The external data source may be either a SQL Server or a State Server service.
Out-of-Process state management requires that "all objects" stored in session are serializable.

Off Indicates that session state is not enabled.
Inproc Indicates that session state is stored locally.
StateServer Indicates that session state is stored on a remote server.

SQLServer Indicates that session state is stored on the SQL Server.