Do not give your email id and password to any web site unless you know for sure what you are doing

I and my friends have received invitation from seemly friendly email from friend email to join them such as the "Desk Top Dating".

When you receive the email, delete it immediately and do not follow through it. This is a trap!

Generally, for any email/web site asking for login/password for another email account, don't follow through that and delete that email unless you know you are giving information to a well trusted email service such as google. Otherwise, you are in danger of exposing your complete email contact list to an unknown user/web site.

For example the mentioned "Desktop Dating" email, this is what the hacker site was doing:

1. in the email it ask you to input your email id (for example yahoo) and password,
2. the "desktop dating" site could use your yahoo email id and password and login to your email account and (don't be fooled by the encryption of the password that shows on the page)
3. read your emails and
4. fetch all your email contact and send the chain email to all your contacts.
5. The cycle continues back to step 1 for all your contacts and their contacts again and again unless you stop it from step 1.

If you already input your email id /password to site like that, change your password now, inform your friends do not open that email from you etc.