A specific request to remove an email address from a specific list, or from all lists operated by a single owner. Also, the process of adding an email addresses to lists without the name’s pre-approval, forcing names who don’t want to be on your list to actively unsubscribe.

Combining Email Marketing with Other Types of Marketing
Whether you choose to do your marketing online or offline, one thing does not change. This is the concept that no single marketing strategy will be as effective as a combination of two or more marketing strategies.