How do algorithms work?

Algorithms have a huge influence over our online experience, shaping what we see and how we experience online spaces

Written by spunout


The things you do online, from clicks on websites, to the messages you send, to who you interact with and when, may be recorded in some way and used to tailor your online experience. This is done through a type of computer code called an algorithm.

What is an algorithm?

An algorithm is essentially a set of steps that tell a computer how to do a particular task or solve a problem. There are a number of different types of algorithms. One of the algorithms people talk about most often are machine learning algorithms.

Machine learning algorithm

Standard algorithms repeatedly follow the same set of instructions. Machine learning algorithms rewrite their instructions based on data they are exposed to. This means they learn from experience. The more you do online, the more information it will have on you and your interests.

How algorithms work

There are a few ways algorithms can shape your online experience:

Targeted ads

Targeted advertising is online advertising that focuses on your specific traits, interests and preferences. This information is gathered by tracking your activity online. Advertising sites do this a number of ways including by:

  • Using cookies
  • Checking your search engine history
  • Getting information from your social media

Cookies are files that a website puts on your computer. When you go onto another website it will detect these cookies from the previous website and place ads based on this. You might notice this when you are on an online shopping website. You’ll probably see ads related to what you were looking at on a specific website for the next while.

Search engines and social media sites can use machine learning algorithms to build a profile of your traits and preferences. They base this on your previous search history. This information is then used to only show you ads that relate to your preferences.

What appears on your social media feed

Each time you do something on social media you are teaching the machine learning algorithm about your preferences, deciding what to show you on your feed, what friend suggestions you might be interested in, and what ads you should see. It uses information based on activities such as:

  • What kind of posts and media you interact with
  • The information you have on your profile
  • What groups or lists you’re in
  • What hashtags you use on some sites
  • Who you are friends with or follow

The more you use a site the more specific and tailored your experience will be.

The news you read

There are different ways to access news online:

  • Through a search for something specific on a search engine
  • By directly accessing a news site
  • Through social media
  • Through a personalised news portal such as Google or Apple news

All these ways of accessing news can be influenced by algorithms. Different content will be prioritised on search engines depending on your location. Content you see on your social media is tailored to you and your interests including the news you see. Similarly if you use a news portal like Google or Apple news an algorithm will prioritise news that it thinks is more relevant to you.

This can result in something called an ‘echo chamber’. This is when a person is only exposed to ideas, people, facts, or news that fit in with their own beliefs or opinions.

Can you avoid algorithms controlling your life online?

There are some things you can do to prevent sites from knowing so much about you, and personalising the experience you have online.

Clear cookies

In your browser settings you can clear all cookies. This will temporarily clear all this information. You will start building up cookies again as soon as you go on another site, however. If you do this, any passwords you have saved or accounts you have logged in will be logged out.

Delete advertising preferences

On sites like Google and Facebook you can access what advertising preferences they have saved about you. You can delete the ones that don’t apply to you, or delete all of them if you don’t want personalised ads at all.

Adjust your privacy settings

Some websites give you the option to choose what information they do and don’t collect about you. In some cases, this can be found when you visit a site and the cookie notice pops up. If there’s a ‘More options’ button, you may be able to choose what is and isn’t collected. You can also take a look at your privacy settings on accounts you log into online.

Look up people and news sources that you know have a different opinion to you

It might seem like your opinion is the most popular opinion but that’s because algorithms have tailored your social media feeds and often your news sources. Make a pointed effort to access content outside of your beliefs and opinions. Reading content from people or publications with different opinions to your own won’t necessarily change your opinion. However, It’s good to try to understand people with very different views.

Be aware of it

Algorithms play an important role, and in some cases they can help to improve privacy and security online – for example, by showing age-appropriate content if the site knows you are under a certain age.. You can’t always do much about it, but try to be aware of the influence algorithms have. Simply by being on social media, you are more likely to be exposed to a broad range of views, but be aware that you’re more likely to see things you agree with, and it can be a good idea to question this every once in a while.

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