Internet cookies are small text files (255 characters or less) that are placed on your web browser or computer by web servers.
A cookie is created when you first visit a site that wants to store information. This text file usually includes a name, an expiration date, a coded number, and the domain name of the visited site.
When you return to a site, the cookie tells the site that a computer with code XYZ has returned and reminds it of your activities and preferences on your previous visits.
These details can include pages visited at the site, what you did when you were on the site, how many times you visited the site, language preferences, the IP address of your device, and your login information.
The information collected from cookies enables websites to offer convenient logins and authentication, personalized experience for you through preference setting and language setting, enhanced online shopping experience, ad management, and more. So in and of themselves, cookies are not bad things.
Cookies, for example, do not store any of your personal information such as your email address or phone number. However, because they allow third-party sites to track you across the web, there can be a downside to cookies , particularly if you are concerned about what some refer to as “targeted advertising” and others as “online spying” or “invasion of privacy.”
Types of Cookies
When a website sends the requested information to you, it also sends your web browser a cookie to help it track what was sent and how. This can be either a session cookie which is only for the specific visit or a persistent cookie that is saved in the web browser for an extended period of time.
Session Cookies – Session cookies help websites to recognize you and remember the information provided by you as you move from one page to another within the same website. For example, e-commerce sites use session cookies to remember the items you place in your shopping cart as you go from one page to another on the site. Without session cookies, your shopping cart will be empty upon “Checkout” since your shopping activities on prior pages will not be remembered.
Session cookies only retain information about your activities during your visit to the site. Once you close the browser, the session cookies are lost and the site will not recognize you the next time you return to the site.
Persistent cookies – Persistent cookies can exist for an extended period of time until expired or until they are deleted. They enable the site to recognize you on a continuous basis. This is done by the web server planting a small text file with a unique ID tag on your computer, while keeping a matching file on the server. On subsequent visits to the site, your browser delivers this cookie over to the site, allowing the site to retrieve the matching file.
Persistent cookies enable websites to remember your preferences and settings (i.e. login information, language selection, font size preference, etc) so that they can offer you a more personalized and convenient access the next time you visit. For security purposes, your login information is generally encrypted by the web server before it gets stored in a cookie.
Cookies by party
Cookies can come from multiple sources. First party cookies are sent directly by the visited site and they are usually identified by the site’s domain name.
Then there are the third-party cookies, which come from those with an interest in the site such as advertisers and ad servers. They are difficult for the average user to identify because they can be connected to any banner ad on a site.
These third-party cookies allow advertisers and ad servers to alternate the ads sent to a specific computer and to track how often an ad has been viewed and by whom.
Cookie profiling and privacy
Cookies are not seen as a direct threat to privacy or security – but they raise a host of indirect issues. Generally speaking, cookies do not contain private data (except for credit card numbers and IP addresses at times) and cannot be used to transmit malware or virus. That’s the good news. The bad news concerning privacy is on the practice of cookie profiling.
Cookie profiling is the use of multiple tracking cookies to track your overall activities online over a period of time and then to compile these data to create a profile of you. The data may include your browsing activities, your demographic data, and some other statistical information. Advertisers obtain the cookies from different sources, usually from popular websites with high traffic volume.
This may not seem like a big deal to some, but it is a big concern for those who take their privacy seriously.
By doing cookie profiling, advertisers can target ads that are more relevant to your interests and buying preferences. Some people may not mind this, while others equate this to “cyber-stalking.”
One of the largest ad servers is Google’s AdSense/Adwords network, which places ads on millions of web pages. Based on a device’s past browsing history and ad clicking history, Google is able to serve ads that closely match the device or individual user’s preferred types of internet content. For example, a car enthusiast might be sent automobile related advertisements, even if he/she is at a site unrelated to the auto sector.
How to manage cookies
Cookies generally do not cause any harm if the sites you visit are trusted and legitimate. Make sure to read their online privacy policies if you are not sure.
If you’re still concerned with what information is collected about you and how your information is shared by the cookies, you have several options when it comes to cookie management.
At the basic level, most browsers let you delete either individual cookies or to remove all of them. You can also choose to set up your browser so it only accepts first-party cookies, which will make it easier to log in to the sites you regularly visit, but will not leave you open to third-party advertising tracking cookies. For instructions on disabling cookies, visit www.usa.gov/optout_instructions.shtml.
There are also cookie managers and browser plug-ins such as “Firecookie”, which enable you to view and manage cookies in your browser.
Computer users in the United States can also opt out of third-party cookies by going through www.aboutads.info/choices/#completed. In the EU, first-time visitors to a site are sent a popup notification of cookie use and given an option to change the settings.
Beware of the supercookie
Not all cookies are created equal and stored in the same location. Supercookies, also known as flash or zombie cookies, are stored either online or in the users’ computer – outside of the usual location in the web browser. This makes them difficult to detect or manage using the standard cookie management tools.
Some of the information provided on this article was taken from the sources below. You may also refer to the sources below to get additional information on cookies and how to protect your privacy online: