What are browser cookies?
Cookies represent a small piece of information – text only, to be precise. Their main purpose is to make your device identifiable to the website, and your browsing experiences better the next time you visit. In the early history of the Internet, they were known under the name “magic cookies”. After the Internet took off and the HTTP (and later HTTPS) protocol became the norm, they became known as HTTP or HTTPS cookies or Internet cookies.
The cookie data is generated on the server the first time you load the website. Your device and the web browser gets a unique user ID (name) or session ID (value), and sometimes an additional name/value combination or a zero. To clarify, the next time you visit, your web browser will “hand over” the authentication cookie to the website server. After it recognizes your identity, the website server can fetch data from your previous visit, and thus knows which information to serve you.
What are cookies used for?
Now that you know what they are, here’s how cookies are most often used.
- Session details. This type can recall your login credentials from a previous visit, such as which account you logged in with. It can also recall certain preferences, such as suggest which topics on the website are of interest to you.
- Personalization and advertisement alteration. On top of suggesting similar content, cookies can help you visually change the website. If you disable a certain element of the website (for example, hide one section of the website you don’t want to see), the cookie saves it. Additionally, you’ll notice the advertisements will go from generic to something you might need. The website uses your browsing habits to fine-tune the ads for each visitor.
- Tracking. Shopping websites store the information about items you visited, added to cart, spent a lot of time viewing, or previously purchased. Additionally, you’ll notice that the items in the cart will still be waiting for you the next time you visit.
- To save money. This one is simple – the more information the website can store in your internal memory, the less storage they need themselves. This becomes obvious with websites that have billions of viewers, such as Google or YouTube.
Browser cookie types
Although there are variations, cookies can be sorted into two types:
- Session cookies. Also called in-memory cookies or temporary cookies, they’re active while you browse. Because they have no expiration date, the browser knows to delete them as soon as you close the program/app.
- Persistent cookies. These don’t go away after you close the browser, although they do have an expiration date so they’re not permanent. They’re what keeps you logged in on different websites so you don’t have to do it repeatedly.
We can also sort cookies further into types you’ll encounter most often, although there are others.
- First-party cookies. They’re generated by the website you visit and are rarely malicious unless you visit sketchy parts of the Web.
- Third-party cookies. These aren’t generated by a website you visit but are served to you nonetheless. The most common form is targeted ads (persistent cookies), which track your browsing and shopping activities. These are a huge privacy concern and, once again, can be malicious if you visit websites with a sketchy reputation.
- HTTPS cookies. They’re used by websites with an HTTPS security protocol that encrypts data. They prevent eavesdropping on sensitive information such as payment details, login credentials, etc.
- Zombie cookies. These are the scariest types of cookie and s huge privacy concern. However, they have genuine use, such as banning a user from visiting. The website can install these even if you opt-out of accepting cookies. They regenerate automatically even after you delete them. Unfortunately, web analytics and advertising companies often abuse them to track your Internet browsing habits and nudge you into clicking on targeted ads.
Where are cookies stored?
The majority of cookies are stored locally, on your device. This means you can delete cookies at will. And, while this can degrade the browsing experience, it can also help you get rid of those that are sketchy or downright malicious. If you do, the next time you visit, you have to accept the new cookies. You can also change your browser’s settings to enable or disable cookies entirely, although the latter has consequences. Some websites will stop working altogether, while others won’t let you log in or perform certain things.
The exception is session cookies since the browser stores them in the RAM. They’re crucial to anonymity browser plug-ins and extensions as well as private browsers for secure browsing. The better option would be a reliable VPN service for Chrome (and other browsers) or a browser with a VPN.