These are word's examples related to unsubscribing. Click on any word to go to its word's detail page. Or, go to the definition of unsubscribing.
As a result, tasks such as subscribing and unsubscribing are only handled by sending mail messages.
The emails do contain a link for unsubscribing from their solicitations.
For years, end users have been told not to trust email unsubscribe links, so many users hit the spam button as an alternative to unsubscribing.