A marketing website is a website that engages users in some kind of interaction that aims to bring them closer to a direct purchase or other desired marketing outcome (e.g., newsletter subscription, inquiry, product trial).
Unlike a corporate (brand) website, which aims to build image and goodwill, a marketing website is transactional and sales-oriented (also called an e-commerce site). These sites are heavily focused on user experience (UX), clear calls to action (CTAs), and accurate conversion tracking.
