In this article we will learn about how search engines work. Almost everyone who have used the Internet before would have used the search engine to find the information that they are looking for. Do you know that there are billions of pages on the web? Yet it normally only takes less than three seconds for search engines to receive your search queries, process them and return the result to your browser. How do the search engines do this? Keep reading to find out.
Before we answer this question, we need to know what a search engine is and who are the largest search engines in the world. A search engine is just a website – just like any other website – that performs a special function to its users, ie. to help the users search for information on the web. As for any other websites, user experience is very important and hence the search engines will try to return the search result to the user in the fastest time that it can. This is not an easy task as there are literally billions of websites and web pages in the world. The search engines need to return the result not just randomly but in a specific order. Preferably they would find what they need when they click on the first result returned so they do not need to keep searching.
The largest search engine in the world is Google, who processes about 70% of all the searches performed on the Internet. The two other major search engines are Bing and Yahoo. There are a couple of others search engines such as Ask.com but they are getting less prominent compared to Google, Yahoo and Bing.
So how do the search engines do this? You need to know that most of the time the searches are not performed “real-time” (there are exceptions for this such as news or stock price update). This means the search engines actually have a very large database in their own network all over the world. This database is kept being updated regularly to stay fresh, so when the search engines query them it would get the latest and newest result. How does this database get populated? There are a number of processes that search engines do:
1. Crawling the web regularly to gather information from all around the web. This would include finding new pages that just come up, or removing the websites which no longer exist its database
2. Indexing the web pages based on the content and the links to and from the pages. This is to determine what the page is about, so when users search for specific term it can then be compared to the keywords which explain what the page is about. This is why keyword research is very important for search engine optimisation
After the database is ready, the search engines are ready to serve the users. When a user types in a search string in the text box, the search engines do the following:
1. Processing the query. The searched keywords are received and compared against the keywords in the database. Keep in mind that it is almost impossible to have all the possible keywords combination in the world as different people type in different search queries even when they search for the same thing.
2. The search engines then look for the best match in their database, by calculating the “likeness” of the search queries in meaning to the keywords of each web pages indexed in the database. This is to determine the relevancy of the page in regards to the search query. There are complex calculations and formula included in this process, mostly related to the latent semantic indexing. The search engines are constantly improving their algorithms and techniques for this process to make the result more accurate.
3. Retrieve the result and serve it to the user. This is the easiest part of the process. It is just the matter of returning the result and formatting it in a certain way to the users on their browser. The returned results typically include the main title, the URL, and the short (limited) description of what the web pages are about. Users will glance through this list quickly (typically 10 results per page) and try to find the best information that they want.
The following video from Google shows an explanation of how search process works:
So this is how the search engine works in a nutshell. Obviously there are many complex algorithms involved but the above are the main processes that can help a user to know.
The next question you might have in mind is, if you have a website, how do you make it rank on search engine search result pages (or commonly known as SERP)? The process of helping your website to rank better on SERP / search engine result’s pages is known as SEO (Search Engine Optimisation). This is a huge topic by its own and we have previously written an article about this. You can read about SEO basics here.
The next step after understanding is to find a qualified SEO professionals or consultants that can give you quality and reliable advice about your website. They should be able to give you advice on how to improve your website performance for a better search result. It is important to find someone who really knows what they talk about, ask for clear explanation about what sort of activities they are going to perform for your website. Although some of the bits and pieces could be technical stuff that you might not understand, ask them still the high level processes and see if they are willing to give out the information. If they are not, it is likely that they might not truly understand about hoe the search engines work and how to properly optimise the SEO for a website.
This article is written by our expert staff at the Wollongong SEO company. We hope this article has been helpful to you to understand how the search engines work.