Limited time offer










Search blog

Subscribe to RSS


Cookies – what are they good for?

A few years ago the use of cookies to track users’ online activity created a bit of storm which led to changes in the law. There’s nothing inherently malicious about cookies but inevitably a few organisations over stepped the mark and thought it was alright to track your every move without you being aware of it. Read on to find out all you ever need to know… and probably a little more too.

Are cookies evil?

You might have heard a lot of negative things about internet cookies, like they stalk you across the internet (and even in your sleep some would say), record your every online move and send it back to an anonymous omniscient controller who stores the information for a future sinister reckoning. Not so.

What is an internet cookie?

When you visit a website or open a certain type of email a cookie is created on your web browser. A cookie is essentially a simple text file that stores information.  This allows your browser to access the cookie and pass data back to the original website.

Cookies… the benefits

Think of a cookie like a little bit of digital memory that is unique to you. When you visit a website it remembers your personal details. This could be a password to access the site and other browsing preferences such as language and geographical location.
A cookie also helps ensure that a web page does not ask for the same information multiple times. This is useful as it negates the need to login multiple times as you navigate from one page to the next.
Another point is that cookies provide business and marketing information about you to the site. This could be information you have entered or a history of your page browsing.
From the web site’s perspective the aim is to provide you with content that you’re interested in. This is determined by your previous browsing history stored in the cookie. For instance if you visit a retail site and bought shoes you’re likely to receive content that focuses on shoes.

Information collected by cookies

Cookies capture quite a lot of information but they are not able to collect or steal your private information.  Essentially they track behavioural information such as the pages and content you look at, when and how often you visit the site, what you search for, whether you clicked on an ad or link, your geographic region, language preferences, and features from of the device you are using.

BullGuard protects your computer from malware


Tracking cookies – borderline evil?

Tracking cookies are like normal cookies on steroids. They typically work across two or more unrelated websites.
Imagine that you visit a website that also hosts advertising from another company. As an advertiser on that site the company has the ability to place a cookie on your computer. If the advertiser does this and you visit another website with the same advertising the company will know that you have visited both websites.
Nothing malicious has happened (we hope) but the advertiser is able to determine all the sites you visit if they have cookies present on those sites.

Do cookies carry malware?

In short, cookies are generally safe. They simply store information that you have entered or they receive from your browser and this information is only available to the website that you were visiting.
But, there is potential for them be used for malicious purposes such as spyware. That said, cookies recognised as spyware are swiftly dealt with by good security software such as BullGuard Internet Security.

Different types of cookies

Here are some different types of cookies:
  • Session cookies – Also known as transient cookies and are the ‘good guys’ of the cookie world. A session cookie is stored in temporary memory and remains available for the duration of your active “session” within the browser. When you close your browser it is automatically removed from memory. On your next visit to the website, you won’t be recognized.
  • Persistent cookies – These are the most common type of cookies and are stored on your computer’s hard drive. The cookie remains on your device until it reaches its expiry date. At this point the browser purges the cookie from the hard drive.
  • Third party cookies – As mentioned above third party cookies are files that install on your computer by a website that is different from the website you are actually visiting.
  • Http only cookie – Very similar to a normal cookie (as above) except it contains a special ‘Http only’ flag which instructs the browser to restrict access to the data. The flag is used for transmitting http or https over the internet.
  • Flash cookies - Flash cookies are independent of the browser. Written by Adobe Flash they are designed to be permanently stored on your computer. A Flash Cookie could be created when you visit any site that uses Flash on its pages.
  • Zombie cookies – so called because they rise from the dead. Zombie cookies come back to life after you kill or delete them.

Privacy implications

Cookies have got a bad name because of the largely invasive methods used by some companies thanks to Zombie and Flash cookies, and to some extent third-party cookies.
However, thanks to a swelling tide of outrage at some companies running a railroad through the concept of privacy, laws have been enacted that put an end to these questionable practises.
That said there are still some who use cookies to scoop up your data without asking. But by and large cookies are not malicious, not even tracking cookies, and they’re certainly not harmful like malware is.

Keeping them out

If you’re not happy with cookies stalking you there are steps you can take:
  • Opt out of cookie tracking – most websites let you know when they’re using cookies
  • Check your browser’s privacy settings. Most browsers have settings, which allow you to establish your preferences allowing you to delete or block them from your computer
Use a free tool like CCleaner to periodically delete cookies from your computer
Filed under: Tips and tricks

Written by Steve Bell

Steve has a background in IT and business journalism and has written extensively for both the UK national and trade press including The Guardian, Independent-on-Sunday, The Times, The Register, MicroScope and Computer Weekly. He's also worked for most of the world's largest IT companies producing content producing. He has a particular focus on IT security and has produced several magazines in this area.

More articles by Steve Bell

Leave a Reply




Please enter the code

Please enter the captcha code!

Security code

Ranked #1 by industry experts

BullGuard Internet Security Cup

Internet Security

Free download
We use cookies to ensure that we give you the best experience on our website. By continuing to browse, we are assuming that you have no objection in accepting cookies. You can change your cookie settings at any time.