What are the different modes ASP.NET sessions can be stored?

Asp.net session can be stored in 3 different modes:
1. In-Process
In this mode state is stored in asp.net worker process (aspnet_wp.exe). This is the default mode. The disadvantage is if IIS is restarted state will be lost.
2. State Server
In this mode state is stored in state server (which solves the IIS restart issue as the state server(aspnet_state.exe) can be kept in a separate machine). In this state is serialized and stored.
3. SQL server
Here state is serialized and stored in sql server.

www.codecollege.NET