In response to a query regarding site structure, Gary Illyes of Google highlighted the benefits of a hierarchical site layout for SEO.
Gary provides solid justification for both the advantages of a hierarchical site layout and the suitability of a flat site structure for straightforward websites.
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Level Site Architecture
Every page on a flat site structure contains a link back to the main page, making it so that you may access every page from the home page with only one click.
The reason it’s termed a flat structure is that, if the linking structure were shown, everything would be connected on a single level below the home page.
When online directories and reciprocal linking were the main sources of links, the flat site structure emerged (when two sites agree to link to each other).
As part of the SEO approach, a flat structure site structure was used to distribute PageRank evenly across all pages, maximizing their potential to rank. This was significant because, at the time, the website with the highest PageRank was ranked top.
In the end, Google reduced PageRank’s significant impact as a ranking criteria, increasing the likelihood of relevant sites with lower PageRank scores ranking.
That modification eliminated almost all justification for employing a flat file structure.
Site Structure in Hierarchies
Within the framework of a website’s structure, a hierarchy is a method of arranging content from the broadest level of the site topic down to progressively more specialized subtopics.
The homepage represents the top level of the hierarchy, with categories and sites descending from it offering ever more specialized content in a perfectly structured hierarchy.
By structuring their content in this way, publishers can establish subject-based categories—what SEOs formerly referred to as “themes” or “topic themes,” but now just call topics.
For instance, the home page might feature the theme of the entire website, such as Science. Subcategories such as Astronomy, Botany, Geology, Meteorology, and Psychology can be found at lower levels.
Regarding the Astronomy category, the subjects of Astrophysics, Cosmology, Observational Astronomy, Planetary Science, and Stellar Astronomy may have more specialized subcategories.
Articles about the same subject matter are found at the category and/or subcategory levels.
Also Referred to as the Taxonomic Site Framework
Another name for the hierarchical site structure was a taxonomy site structure. It was claimed that well-known web directories from the early 2000s, such the DMOZ Open Directory Project, were set up using a taxonomical site layout.
The primary topic (Web Directory) was represented by the home page, from which progressively more specialized categories, subcategories, and web pages are linked.
Taxonomic Site Architecture in the DMOZ Directory
The pyramid site structure is another name for the taxonomic site structure.
The Pyramid site structure was also used to illustrate taxonomic and hierarchical site structures. The home page is at the top of the pyramid, and the ever more specific categories, subcategories, and web pages are below it.
Pyramid Site Layout
Structure of the Silo Site
A Silo site structure was a fourth method of visualizing site architecture that was developed contemporaneously with the first three.
The ilo site structure was created in the early 2000s as an alternative method of visualizing website structure. Bruce Clay, one of the first SEOs to come out of the old school, is credited with creating it, which may surprise some SEOs.
Similar to the first three site structures, this one is divided into silos, with a basic theme at the top and more specific categories, subcategories, and web pages descending the site hierarchy.
Site structure of Silo
Site Structure: Hierarchical, Taxonomic, Pyramid, and Silo
There is a distinct depiction for every type of site structure. However, they all outline the same hierarchical structure for classifying topics on a website, starting with a general topic at the top and moving down a hierarchy of categories and sites to more detailed topics at lower levels.
All of them represent the same concept, which is a hierarchical site structure, in different ways.
By now, it should be rather evident that a taxonomy, silo, or pyramid site structure is simply a different way of presenting a hierarchical site structure, which is a logical and necessary method of structuring a website. None of these site structures are particularly creative, special, or magical.
Which Type of Site Structure Is Better, Flat or Hierarchical?
The queryer posed the following query:
“Which category structure should my website have—a flat structure or a hierarchical one?”
In response, Gary Illyes said:
“I believe the scale of the site has a major role in this.
A hierarchical structure is probably preferable for a large site because it will let you do interesting things with a single section and possibly even allow search engines to handle different portions differently, particularly when it comes to crawling.
Search engines might crawl /news/ more quickly than the other directory, for instance, if it included a /news/ part for newsworthy stuff and /archives/ for older content. It’s barely doable if you put everything in one directory.
Site Structure in Hierarchies
Gary provides a compelling case for using a hierarchical site structure, pointing out that it allows Google to handle various areas of a website differently, such as classifying a particular section as news-related. A webpage’s categories can each relate to a distinct subject, which aids Google in segmenting the site and understanding the purpose of each portion.
SEOs had to give the hierarchical site structure four names since it was so good.
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