If you already have a pretty large database, you also likely have some contacts that have gone quite stale. If so, I recommend running a re-engagement campaign that can help you both scrub your list and prevent the kind of spam and IP issues I addressed earlier, as well as reawaken old contacts that might have forgotten about you, but would actually be great fits for sales.
A tracking pixel is a snippet of code that allows you to track your subscribers’ activity across various channels like your website, landing pages, and newsletters. Then, you also have the option to send emails triggered by certain behaviors. So for example, if a subscriber goes to your site and checks out your product page, a tracking pixel can send an email with a special offer for the specific product the viewed.