Difference between Asp.net SessionState and ViewState in C#, VB.NET

View State: 

• View state is maintained in page level only.
• View state of one page is not visible in another page.
• View state information stored in client only.
• View state persist the values of particular page in the client (browser) when post back operation done.
• View state used to persist page-instance-specific data.

 Session State: 

•  Session state is maintained in session level.
• Session state value is available in all pages within a user session.
• Session state information stored in server.
• Session state persist the data of particular user in the server. This data available till user close the browser or session time completes.
• Session state used to persist the user-specific data on the server side.

 Usage

• If you want to access the information on different web pages, you can use SessionState
• If you want to access from the same page, then you can use Viewstate

Security

•      Session state provides more security when compared with view state as the data value is stored in server side