How do search engines distinguish between subdomains and root domains?

Here’s a summary of how search engines treat subdomains and root domains:

Crawling and Indexing: Search engines crawl and index subdomains and root domains separately. Subdomains are treated as distinct websites, and their content is indexed independently of the root domain.
Ranking: Subdomains may not fully benefit from the backlinks and authority accumulated by the root domain. This is because search engines treat subdomains as separate entities, and the link equity from the root domain may not be directly passed to subdomains. However, subdomains can still benefit from the root domain’s authority through co-citation and co-linking.
Trust and Authority: Root domains influence the overall domain authority, backlinking, and page rank. Subdomains can leverage this authority, but their own authority and ranking potential are separate from the root domain’s.
Use Cases: Subdomains are suitable for niche content, such as blogs, customer support pages, or testing environments. Root domains are typically used for the main website or primary brand presence.

Key Takeaways

Search engines treat subdomains and root domains as separate entities for crawling, indexing, and ranking purposes.
Subdomains may not inherit the full authority of the root domain, but can still benefit from it through co-citation and co-linking.
Root domains influence overall domain authority, while subdomains have their own authority and ranking potential.

Note that these points are based on the provided information and may not reflect the full complexity of search engine algorithms. However, they should provide a general understanding of how search engines treat subdomains and root domains in terms of ranking and indexing.