A root domain is the main domain in a web address, excluding any subdomains. For example, in the web address "example.com," "com" is the top-level domain, and "example" is the root domain.
The root domain represents the primary web location, and subdomains are extensions or subdivisions of the root domain.
In the URL "blog.example.com," "example.com" is the root domain, and "blog" is a subdomain.
Ensure proper management of subdomains, consider SEO implications, and use subdomains for organizational purposes when appropriate.