Gmail

https://www.youtube.com/watch?v=J3C8uT-KHcw



Google automatically scans emails to add context-sensitive advertisements to them. Privacy advocates raised concerns that the plan involved scanning their personal, private emails and that this was a security problem. Allowing email content to be read, even by a computer, raises the risk that the expectation of privacy in email will be reduced. Furthermore, email that non-subscribers choose to send to Gmail accounts is scanned by Gmail as well, even though those senders never agreed to Gmail's terms of service