In this article, you know why the security of intelligent contacts is needed, why the stench is needed and how functions are to be used.
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A subdomain is a domain that is part of a higher-level domain. Most often, it belongs to the 3rd or 4th level. His name includes the name of the site and his own name. For example, in the case of the site freehost.com.ua, the subdomain will look like this: subdomain.freehost.com.ua. Having learned what a subdomain (subdomain) is, you need to understand in more detail the possibilities of its application, which we will talk about further. Subdomains are mostly used by large portals that branch out the main domain name of the site through the use of subdomains. The fact is that such projects have many large sections that are separated into separate sites for greater convenience. This is often practiced in online stores, where each section can be considered as a separate project. As a result, in the search results, each of them is located on a separate subdomain: when we click on one of the links, we get to the corresponding section, where we can quickly find all the necessary products. This address belongs to a level 4 domain.
A subdomain is a separate site on which you can host a forum or technical support, separating them from the main project. This is most often the case for thematic resources; On subdomains, you can display sections that must be closed from indexing; Separately, you can bring out the mobile version of the site or separate sections available in another language; To simplify the promotion of the project, which seeks to occupy its niche in different cities. The fact is that it is easier to promote 10 sites in different regions than one big project across the country. But here you need to take into account that the Google search engine does not issue the root site and its subdomains in one request. It distinguishes between them only if the subdomains have been registered in its directory. It is equally important to approach the preparation of the semantic core responsibly so that keywords are not repeated. It should be taken into account that if the main site is affected by filters from search engines, then the restrictions will affect all its subdomains.
A DNS meta query spider that enumerates DNS records and subdomains supports an API.
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