These days, many new social networks are getting desperate to increase their registered user-base. They encourage their existing users to invite their friends to join that network by running a sort of points or rewards system. Some of them even offer cash rewards.

Now I recently noticed that worlds top social network Facebook is also encouraging existing users to invite their friends. Of course, there is no cash rewards of any kind for it. They just display a “thank you” note on your Facebook home page once you invite enough number of users. I do not know exact number of invite you need to send but its seems well above one hundred.

Please note the difference. You have to invite them via using email addresses. If you go on adding existing users by visiting their profiles your Facebook account may get disabled.

Also it is not about number of invites but number of people accepting your invitation.