We all use it, I’d say, daily. It makes your life so much easier. Personally, I couldn’t live without it. But how do search engines actually work? How does a search engine know what the most relevant result is for me?
In this article I will only give information about Google. Google is the #1 most used search engine worldwide and I think it’s safe to say that anyone will know it (apart from the few people who have lived under a rock for the last few decades).
Let’s start at the beginning
Search engines find the right content for your purpose. It’s kind of like shopping for make-up. You will tell the salesperson what you need and they will find the right brand and color for your skin and skin tone.
To get a result after you search for something, Google needs to know what websites there are. Google does this by ‘crawling’ webpages: there is a starting point and then the ‘crawler’ (or spider) goes through the entire internet using links from one page to another: they are crawling their way through the internet, page by page. By making copies of these pages, they gather the content.
Once they have gathered and copied the content, they don’t know what it is or what to do with it. So the next step is to understand this content. This is called indexing. Through indexing a webpage, Google can find out what a website is selling, what the main content is about or where their office or shop is located.
So when you are searching for ‘best ice cream in Rome’ using Google, you will get results for all different gelateria’s in this beautiful city. Google will show the reviews given from customers and they will most likely give you webpages which will link the ‘top 10 best ice cream parlors’. There are 200 signals Google looks at to determine which webpage will have the best result (for you). From titles, keywords, and pictures to meta descriptions and the performance of a webpage.
Google also uses PageRank: the higher webpage scores in PageRank, the higher it will show in the results. Webpages get good PageRank ratings by having other high rating webpages link to their page. Somewhat of a popularity contest. Google PageRank doesn’t look at keywords or content, it’s all about the links.
Okay, now we know webpages are being crawled and indexed. Google knows what the content on a particular webpage is about and how it can help you. Using this and PageRank, the algorithm kicks in. Algorithms are being kept secret by all search engines, so we don’t know exactly how they work, but they do. The algorithm decides which page will rank first, second and so on whenever you type in what you are searching for in Google.
The algorithm is the final step for Google to get you what you need.