Opt-out
With the opt-out system, recipients are automatically signed up for an e-mail newsletter, after which they have the option to unsubscribe from it (opt-out). This allows a company to distribute emails to customers, for example.
Opt-out is not entirely uncontroversial. Because the recipient has not given prior permission to receive messages, they may be perceived as unwanted. Opt-out is also widely used by spammers, who collect e-mail addresses from a variety of sources for their bulk e-mail.
When there is prior agreement to receive e-mail we speak of opt-in.
The opt-out principle is also used in direct mail and telemarketing, the commercial solicitation of potential customers by mail and telephone, respectively.
