Subdirectories and subdomains can be used to organize web content. What are they, and how are they used?
The following is my understanding.
Let’s imagine a site called site101.tld101. In such a case, tld101 is the top-level-domain or tld. The domain, aka root domain, is site101.tld101. Furthermore, site101.tld101/blog is a subdirectory.
Imagine then the address uppersite.site101.tld101. In that case, uppersite is a subdomain.
Subdomains, it seems, are seen by search engines as separate sites from the domains they are hosted on. A subdomain, therefore, can be used to host separate content from what’s on the root domain. A subdirectory, on the other hand, is treated by search engines as part of the root domain site.
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