Each web server is given its own IP address, which always consists of four ranges of numbers separated by dots. An IP address could look like this: 22.214.171.124.
However, such number combinations would be quite difficult to search for, as they are hard to remember and their entry would be very error-prone.
For this reason, IPs are replaced by domain names. Each domain is unique and helps to separate areas of the internet from each other.
Let's take a look at the Searchmetrics domain:
The entire name of the domain is also called a "fully qualified domain name" (FQDN). If this is entered as a request in the address line, the domain name is converted back into the assigned IP address in the background and returned as such to the browser so that it can call up the page correctly and knows where to find it.
- Components of a Domain
- Should i use Subdomains or Directories?
- Analysis in the Searchmetrics Suite
Components of a Domain
Each domain consists of several parts that are separated from each other by dots.
Basically, there are always three different levels:
1. Top Level Domain (TLD)
The TLD describes the domain ending (e.g. ".de" , ".com", ".ch" etc.) and thus forms the highest level of name resolution. Basically, TLDs can be divided into two groups:
- Country code TLDs: include all TLDs associated with a specific country (examples: ".de", ".ch", ".nl" etc.).
- Generic TLDs: All TLDs that are not associated with a specific country or geographical location. (Examples ".com", ".org", ".net", ".eu" etc.).
If we look at our example domain, ".com" is the Top Level Domain:
Often, country-specific domains achieve higher rankings in the respective countries, as search engines automatically classify them as more relevant for the countries.
However, generic TLDs can also be assigned geographically by Google Webmaster Tools, which increases the chances of also ranking with international TLDs.
2. Second Level Domain (SLD)
In front of the TLD is the SLD, the actual name of the domain, which can be defined completely freely by the owner.
In our case, the SDL is the "searchmetrics.", i.e. the brand name, in the middle of the domain.
3. Third Level Domain
With the help of third-level domains, website owners can use subdomains to separate information and content from the main domain and divide it into different areas. Wikipedia, for example, divides its offerings into different languages. The domain "de.wikipedia.org" leads to its German-language entries and "en.wikipedia.org" to the English-language entries. It is also typical to create subdomains for shop (shop.example.de) or blog pages (blog.example.de).
We decided to move our Searchmetrics blog to a subdomain. Therefore, its domain is as follows:
The word "blog." therefore forms the third level domain.
In our example domain, we also see that "/us" at the end, indicating the English version of this page. Such endings are called directories.
In the Wikipedia example we have learned that different languages can be separated by different subdomains. With the Searchmetrics example we now see that this also works with directories. So what is the difference between these two variants?!
Subdomains are generally treated as independent domains by search engines. This has the consequence that the main domain passes on almost no authority or trust to the subdomain. However, since search engines can nowadays very well assign subdomains to their "root domains", links between subdomain and main domain do not generate backlinks, but count as internal linking. Subdomains must therefore have their own link-building structure in order to achieve good rankings, which is why setting them up is usually relatively complex and involves a lot of effort.
The main task of subdomains is to separate the topics of a domain from each other and thus to structure them in a meaningful way. They are particularly useful for structuring larger companies that have several locations, each with different tasks, and want to present these on the website. All information on a specific location can then be collected on a subdomain, so that this subdomain also contains only specific information about one location. Furthermore, it can also make sense to store pages in different languages or pages that diverge thematically on individual subdomains.
From the previous sections we already know that the "/us" in our example represents a directory in which the English pages of the subdomain are located.
Unlike subdomains, directories run under the main domain and are therefore not seen as an independent domain.This has the advantage that the main domain transfers part of its authority and trust to the sub-directories. Also, all backlinks that link to a directory pass on authority to the entire domain. Of course, the linking between "root" and directories counts as internal linking here as well.
Directories should always adapt to the URL structure and navigation in terms of content. This way, crawlers can be instructed afterwards to leave out certain parts of your domain from the analysis. This also makes sense from an SEO point of view, as clear names of directories contain keywords that show both search engines and end users what content is to be expected in them.
Should i use Subdomains or Directories?
Whether a subdomain or a directory should be set up always depends on the individual case.
If content is to be considered separate from one another and has little connection to the rest of the domain, these pages should run under a subdomain.
However, if the contents are very close to those of the main domain, structuring in directories is a good idea.
Advantages and disadvantages of a subdomain
In order for a subdomain to rank well, the same steps are necessary as when setting up a new domain. Due to the separate consideration of domain and subdomain, the subdomain hardly benefits from the authority of the root domain. Only individual link-building measures help the subdomain to increase its authority, link juice and trust.
However, this results in another advantage of subdomains: if a subdomain is algorithmically penalised, this does not fall back on the root domain or on other subdomains. The risk of a general loss of visibility is thus spread.
Advantages and disadvantages of a directory
Setting up a new directory is less complex in comparison. Because the main domain passes on its authority, link juice and trust directly to the directories, the optimisation of directories requires less effort. However, for this reason, you are far more limited in the set-up and structure than when creating a subdomain. In addition, it should be noted that the entire domain is affected by an algorithmic penalty. In this case, the directories would also be affected.
Note: When making changes to the existing URL structure, you should make sure that old pages already indexed on Google are permanently forwarded to the new pages via 301.
To prevent duplicate content accusations, subdomains should only be accessible via a path of the main domain. If they are reached via other paths, it is also advisable to use a 301 redirect.
Analysis in the Searchmetrics Suite
Under Research Cloud > Organic Search > Subdomains, all subdomains of a domain are listed. There you can view the respective SEO visibility and the visibility trend of the individual subdomains, as well as their percentage of the total domain visibility, for the desktop and mobile area.
Let's stay with the Wikipedia example: It is clear that "de.wikipedia.org" has the highest SEO visibility and thus accounts for almost 90% of Wikipedia's total SEO visibility. The second most important subdomain is "en.wikipedia.org".
If we click on one of the listed subdomains, we can analyse it in more detail in the Research Cloud.
You can also enter the desired subdomain directly in the search bar of the Research Cloud to analyse its performance.
To analyse the performance of individual directories, navigate to Research Cloud > Organic Search > Directories. On this page you will find a chart that shows the historical SEO visibility of the individual directories. If you ever suffer an SEO visibility loss, the analysis of this chart can provide helpful clues.
Let's take a brief look at this, using an example. We see that especially the directories "/music/" and "/news/" were strongly affected by a loss in October, while the other directories showed relatively constant fluctuations.
Further down the page, there is also a table that provides information about the SEO visibility (and the visibility trend + percent of the total SEO visibility) per directory. Directories can also be broken down to further sub-directories here.