Session Mode and State Provider in asp.net

In ASP.NET there are following session mode available, 

• InProc
• StateServer
• SQLServer
• Custom

For every session State, there is Session Provider. Following diagram will show you how they are related.

Fig : Session State Architecture

we can choose the session State Provider based on which session state we are selecting. When ASP.NETrequest for any information based on session ID, session state and its corresponding provider are responsible for sending the proper information based on user. Following tables show, the session mode along with there provider Name. 

Session State Mode	State Provider
InProc	In-Memory Object
StateServer	Aspnet_state.exe
SQLServer	DataBase
Custom	CustomProvider

apart from that, there is another mode, "Off". If we select this option the session will be disabled for the application. But our objective is to use session, so we will look into that four session State Mode.