At the beginning of internet time, human editors categorised web pages to facilitate search. It soon became apparent that this would be unfeasible, given that the number of webpages available on the World Wide Web is increasing exponentially. Current estimations place the number of web pages at 60 trillion, with more being added every day.

Today, search engines find, analyse and rank web pages according to mathematical algorithms written by super-clever super-geeks. Some well-known search algorithms include Bing’s Tiger, Google PageRank, Google Panda, Google Penguin and (the latest and greatest Google Hummingbird). Now, social media sites – like Facebook – also use algorithms to find and sort data.

How Does Search Work?

Google explains it like this: they navigate the web by crawling pages (following links from page to page), sorting pages by their content and other factors and including it in a massive index (currently 100 million gigabytes in size). Clearly, too big a task for any number of human beings! To help return the best possible results when you type a query into their search engine, the Google Geeks (really smart peops with backgrounds in computer science, physics, mathematics and engineering) have written programmes and formulas to automate and speed up the process. When you ask Google a question, it checks your query against the trillions of pages stored in its index and presents you with the best possible matches.

Why Do Search Algorithms Keep Changing?

The internet is a very different place today to what it was ten years ago, five years ago, even one year ago. To make sure your user experience is the very best it can be, and to keep abreast of a digital space in flux, Google updates or changes its search algorithms from time to time. At the heart of the issue is what Google terms ‘the fight against spam’. We’ve all had that experience when we think we’ve found what we’re looking for, but when we click on the link we’re taken to a ‘junk site’ – very annoying and a waste of our precious time! To keep such low quality sites at bay, the Google Geeks work tirelessly to tweak their algorithms. Good news for you, the user; bad news for nasty, spammy websites!

For a comprehensive look at Google’s search algorithms through the years, check out this infographic:

The Complete history of Google Algorithms

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