The way search engines operate has undergone significant changes over the last decade, and even over the last handful of years.
Think you know how search engines work?
You might need to think again.
Though search engines are constantly evolving and adapting to remain relevant and provide accurate results for users, there are several processes they follow that can help us understand the science behind search engines.
And, crucially, understanding this process can be the difference for website owners and developers between a visible site and a site that disappears into the abyss of the internet.
In a nutshell, search engines work by crawling, indexing, ranking and serving results, processing search queries, and, increasingly, using AI-assisted systems to summarise and organise information, all with the aim of providing the user performing the search with the most relevant and high-quality results. Google commonly describes Search as moving through crawling, indexing and serving results, but in practice there are many systems working together behind the scenes. Source
Now, let’s delve a little deeper into the mysterious mind of a search engine.
Lots of Bots
The worker ants of the search engine world are known as bots or spiders, and their purpose is to continually crawl the vast expanse of the internet, creating an index as they go.
Translated: Bots are discovering pages and following links so search engines can understand what exists online.
For Google, the crawler software is affectionately known as Googlebot.
Googlebot works tirelessly day and night, much like Santa and his elves throughout the month of December, to find new and updated web pages, and add them to its existing database.
However, not all sites that get crawled will be indexed. Google states that it does not guarantee every page will be crawled, indexed or served, even when a site follows its guidance.
This is one of the key reasons why having an understanding of how Google search works will impact how successful and visible your website is.
For example, if the crawlers and indexing systems determine that a webpage features duplicate information, has low-quality content, or minimal content, then it may not index the page, making it significantly more difficult to get found in a search.
Inside Indexing
Once the crawlers have identified a new or updated page, they may index it.
A newly indexed addition will include the web page URL, along with essential information that will help the search engine determine if this page is relevant to future searches. This will include keywords that have been found on the page, to decipher what topic the page is predominantly about.
It’s worth noting that search engines don’t just index the words on a page- they also analyse the relationships between concepts, meaning a page about ‘running shoes’ may also be considered relevant for searches like ‘best trainers for marathons’ even without those exact words appearing on the page.
The index entry will also note what type of content was included on the page, and how recently it was updated.
Finally, the index entry will include information about user engagement; notably, how people have interacted with the page.
Search engine indexes are constantly being updated to reflect changes made to any given website or webpage, ensuring that search results continue to remain current.
Appreciating Algorithms
Algorithms come into play when a search is performed by a search engine.
The complex algorithm works in conjunction with the index to determine which pages on the internet will be most useful to the person executing the search, and these will then be ranked in order.
A number of factors are considered by the search engine algorithm to decide which pages are included in the results, and what order they will be ranked in.
These factors include:
- Relevance of keywords
- Quality of the page
- Amount and quality of links pointing to the page
- Overall user experience (UX) and page experience
- The meaning and intent behind the search query
- The location, language and device of the person searching
Among these, the quality and relevance of links pointing to your page (known as backlinks) carry particular weight, as search engines treat them as a vote of confidence from other websites.
An important point to remember is that each search engine will use a different algorithm, and so the same search words in a Google search and a Bing search may produce entirely different results.
Though we know in a broad sense what an algorithm is looking for in order to provide users with the most relevant and high-quality information in response to their queries, the specific details of search engine ranking criteria are a secret guarded as closely as the elusive eleven herbs and spices used by Colonel Sanders to produce his finger licking’ chicken.
It’s also worth noting that algorithms are not set in stone.
They are continually changing to refine search results, aided by feedback mechanisms such as user clicks and engagement metrics.
Query Processing
When a user enters a search query, the search engine processes the query against its index to identify relevant pages.
This involves, among other things, matching the keywords in the query with the indexed pages. It will also take into account the language and location of the user to ascertain the most relevant results, as well as consider the previous search history of the user where appropriate to help determine exactly what they are looking for.
The device the search was performed on can also impact which results are returned by the search engine, for example, if a user executes a search on a mobile device, then websites that have been optimized for a mobile experience are much more likely to rank well.
Bearing all of these factors in its metaphorical mind, the search engine then hierarchically ranks the pages based on their relevance to the query.
The most relevant and high-quality pages are subsequently displayed on the search engine results page.
As a website owner or developer, getting ranked among the top search results for your niche is the holy grail, since the majority of users won’t look beyond the first page of the search engine results in any given search.
The How and the Why
So now we have an understanding of how search engines work, but why do we need to know this?
Well, anyone who is engaging in any form of SEO is essentially optimizing their website to perform well in a search engine. And, trying to optimize anything that you don’t know the basics behind is never going to go well.
If previous attempts to optimize your website have proved fruitless, you may need to go back to the drawing board.
Beyond Bots: AI in Search
One of the biggest changes in recent years is the introduction of AI-assisted search experiences. Google’s AI Overviews, for example, can provide an AI-generated snapshot of key information for some searches, along with links that allow users to explore the topic further. Google also provides guidance for site owners on how AI features such as AI Overviews and AI Mode work from a website perspective.
A key part of this shift is that search engines have become better at understanding natural language- not just matching keywords, but interpreting what a user actually means. A search for ‘good running shoes for bad knees’ is understood as a health and comfort query, not just a product one.
This does not mean traditional SEO is dead. Search engines still need to discover, understand and evaluate web content. But it does mean that helpful, well-structured, trustworthy content is becoming even more important, because search systems are not only ranking pages; they are also extracting, summarising and connecting information in new ways.
For website owners, this makes clarity essential. Pages should answer real questions, demonstrate expertise, use clear headings, include relevant supporting detail and make it easy for both users and search engines to understand what the page is about.
In Essence
The reality is that the way search engines work is extremely complex, but understanding the basic principles of how a search engine works will be immeasurably helpful for anyone running a website.
If you understand it, you can position your website in a way that encourages search engines to find it and use it in search results, which is exactly how you’re going to get in front of your customers or followers.
Looking for help with your SEO? Contact us to find out how we can improve your website and make it more visible online.
