How to send data from one web form to another web form i n Asp.Net

1. Query strings :

Use these strings to pass information between requests and responses as part of the Web address. Query strings are visible to the user, so they should not contain secure information such as passwords.

2. Cookies :
Use cookies to store small amounts of information on a client. Clients might refuse cookies, so your code has to anticipate that possibility.

3. Session state :
Use Session state variables to store items that you want to keep local to the current session (single user).

4. Application state :
Use Application state variables to store items that you want to be available to all users of the application.