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Subfolders versus Subdomains - Which on to choose for SEO?
Subdomains and subfolders have their own individual benefits from business viewpoint. However, these day?s website owners and webmasters are more inclined towards SEO viewpoint rather than business viewpoint.
Whether I should use Subfolder or Subdomain for my Blog promotion?
If you are going for a blog, then using a sub-folder will yield better results. Search engines will distribute ranking power among other pages on the blog including home page. If your blog is popular and receives plenty of links, then your main domain will benefit from the activities on your blog.
When should I use Subdomain?
Subdomain can turn out as a powerful technique to host a blog or a different sub-site with a completely different business theme.
If your main site is about gaming, then you can create a Subdomain for educational purposes.
You can select Subdomains if you wish to start a new site (completely unrelated to your existing site), and you dont wish to purchase separate hosting or use some other domain name. If your main site is gaming.yoursite.com then you can create a completely different Subdomain as education.yoursite.com OR charity.yoursite.com.
If your Business Theme (for 2 different sections) is different then it is best to choose a Subdomain.
What are the Technical advantages (not related to SEO) of using Subdomain over subfolder?
One of the important things to note is that, if you use cookies/sessions in your site, they only work within one domain. Your subdomain cannot share your mainsite cookies or sessions (* just an example).
For security and privacy purposes, browsers will not transmit cookies to any site in a different domain from the one that set the cookie. They can be shared across subdomains and hosts within a domain, but not from one domain to another.
Subfolder or Subdomain: Which one is better from SEO perspective?
Subdomains have been exploited in the past. There have been several instances where one main site was hosting 1000 different Subdomains. Each of these Subdomains were specifically created in order to score higher rankings for any single targeted keyword.
Therefore, search engines have started to tighten their noose around Subdomains hosted within the main website hosting server. More or less, search engines are treating them just like a subfolder. Google has specifically tweaked its ranking algorithms so that pages from multiple subdomains have lower priority as compared to subfolders (for an existing high ranking parent website).
However, there are no fixed rules here. If you manage to make your Subdomain popular in terms of content and back links, then your Subdomain will score higher rankings. Take for example, Google uses Subdomains for different set of services, for example maps.google.com news.google.com and blogsearch.google.com. Each of these Subdomains have their own content and focus on different services.
If you have 100 Subdomains hosted on the main site, and each one of these Subdomains are informative and useful (i.e. unique content, no spamming, good back links etc) then you can score higher rankings for each one of these 100 Subdomains for their respective targeted keywords.
SEO Definition for Subdomain ? Subdomain is treated as a separate website, which is ?TECHNICALLY connected? with the main site (Google considers technical connection). However, you cannot pass link juice from Subdomain towards Mainsite or vice versa. If you intend to do so, then you have to interlink your Subdomain with your main website.
SEO Definition for Subfolder ? Subfolder can be used as a Subdomain catering to different related topics. Subfolder is very much ?SEO connected? to the main site and any activity (good or bad) on the subfolder can have positive or negative impact on your main site?s SEO rankings. If you are pasting duplicate content on your subfolders, then it will lower the search engine rankings of the main site. Therefore you need to be careful while using subfolders for different sections.
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Whether I should choose Subdomain or Subfolder for a multiple language website? This is one of the most important SEO issues. There are several websites which intend to create multiple language sites hosted on the same web hosting server. We would not delve into details, but we will go through a live SEO example to see whether search engines prefer subfolder or Subdomain when it comes to Multilanguage sites.
a) Log into Google.fr (FRANCE) and search for keyword ?Microsoft?. You will stumble upon microsoft.com/fr/fr/
b) Similarly, log into Google.de (GERMANY) and search for same keyword ?Microsoft?. You will come across microsoft.com/germany/ on the top #1 place.
c) Log into google.jp ( JAPAN) and search for keyword ?Microsoft?. This time you will spot microsoft.com/JAPAN/.
Therefore you can clearly observe that search engines (both GOOGLE and YAHOO) can easily perceive your subfolders as separate sections catering to any particular language. A user searching from France, will find France subfolder on the top #1 position, whereas user searching from Germany for the same keyword will spot ?Germany? subfolder on the top #1 position of Google or Yahoo search results.
Conclusion of the above exercise: You can easily choose subfolders for SEO and there are no negative impacts. Search engines can clearly distinguish between different language sections on the main website and can grant them separate rankings.
If you have some specific business preferences of using Subdomains for Multilanguage site, then you can host your content on different domains. For example yoursite.de for germany and yoursite.jp for Japan.
You can also create Subdomains for different language sites, for example de.yoursite.com or jp.yoursite.com
Therefore, choosing Subdomain is more inclined towards business preferences and personal preferences rather than SEO. You have to decide yourself, whether you should choose Subdomain or Subfolder. If you are concerned with technical issues of ?cookies? and ?sessions? then you have to see whether Subdomain or Subfolder will perform better. If you are concerned with SEO issues then choosing Subfolder will save your time. However, any activity (good or bad) on your subfolder can have positive or negative impacts on your search engine rankings. Therefore you must analyze different issues before selecting Subdomain or Subfolder.