A Subdomain is simply an extra layer of specification added to a website’s second-level domain (SLD). For instance, in the URL “images.home.com“, the “home” layer is the second-level domain, and the “images” is the subdomain.
Subdomains are added to websites in order to direct traffic to a relevant area of a website. They can even be used to direct to a different IP address that the main IP address of the website’s URL. While the SEO impact of adding a subdomain is unclear, it’s generally agreed that Google considers domains to be different from their subdomains, opening up optimisation possibilities across different domains.
