Email marketing is the practice of sending various types of content to a list of subscribers via email. This content can serve to generate website traffic, leads, or even product signups for a business. It's important that an email campaign's recipients have personally opted in to receive this content, and that each newsletter offers something of value to them.
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.