[yellowapple]

Email marketing can also include newsletters and emails to existing customers (in fact, the latter is the vast majority of the "email marketing" I receive).

Of the two above, the latter is probably the spammiest, and might technically count as "spam" since they're unsolicited, but they're generally (in my opinion) targeted sufficiently well enough to be acceptable/tolerable. In excess, though, they can quickly cross that line into being unquestionably spam.

[NoGravitas]

I generally consider "emails to existing customers" to be [bacn](https://www.bbc.com/news/technology-21830739), in that they're neither ham nor spam.