In computing terms, an algorithm is a computer programme based on a set of rules.
In computing terms, an algorithm is a computer programme based on a set of rules. The rules are defined to solve problems, and automate the processing of problem-solving tasks. Search engines use algorithms to discover pages on the web and then rank them in the way that they think is most relevant for people conducting the search.
More about Search Engine Algorithms
Search engine algorithms are complicated and – somewhat annoyingly – seem to constantly evolving. For example, Google uses more than 200 search ‘signals’ to determine where a webpage should rank in its results. And while they will offer some basic guidance, some of these signals are kept secret, and are only discernible by conducting repeated tests against a variety of search variables.
Keeping up with algorithmic changes is a daily, full-time job, and underpins the entire business model of companies like Moz. Google’s dominance in search makes it the natural focus of most attempts to understand search algorithms. It has launched eight major algorithm updates since 2011, each designed to refine and improve its ability to surface the best content for search keywords, ‘punish’ weak or duplicate content, and better understand the intent behind searches.
In 2011 it launched the Panda algorithm update to locate and punish duplicate, plagiarised, and thin content scraped from other websites.
In 2012 it launched Penguin, which sought out pages designed to ‘game’ the algorithm by using irrelevant links and over-use of anchor text.
In 2013 came Hummingbird. It helps Google better interpret search queries and provide results that match the user’s ‘intent’ rather than just mechanically matching the words in the search query. While keywords still factor into the algorithm, Hummingbird allows pages to rank against a query even if they don’t contain the exact words or phrase used in the search. This type of semantic search processes natural language and looks at the search query plus co-occurring terms and synonyms.
Other major google updates include Pigeon (2014), Mobile (2015), RankBrain (2015), Possum (2016) and Fred (2017).
Number two search engine Bing also has a unique search algorithm, however not as much is known about its inner workings or the signals it relies on to decide search rankings.