Gmail, one of the free services is that the to users space free to email offers. Trial version Google on 1 April 2004 was submitted on. this means that each user could have received an invitation from another user that has a Gmail account was the account email and the services it uses. This service on February 7, 2007 open to the public and was, needless to invitation for membership was not on 7 July 2009, the trial mode came out, which at that time has 146 million users per month.