What are cookies on a website?

Cookies are data files that are placed in your computer’s memory when you visit a website. The files can contain a wide variety of information that’s used by websites to personalize user experience.

The site server determines whether a visitor’s web browser should save their cookies. Most browsers have an option to disable the saving of cookies due to possible privacy concerns. 

How do cookies work?

When you visit a website, it sends a string of text to your computer if permission is granted by the user. The files are then stored in a folder and remain there until deleted.

The browser will send them back to the site server during the next visit. Accordingly, the site will use the cookie to craft a personalized browsing experience for the user.

A cookie may contain attributes that set its access permissions:

• Expiration date ‒ sets the time when a cookie is removed from the browser.
• Path ‒ prevents the cookies from being sent to other URLs beside the appointed URL path.
• Samesite ‒ decides whether the cookies are restricted for first-party requests only or permitted for third-party requests as well.
• Domain ‒ specifies which hosts can receive the cookie.

What information do cookies store do and why do websites use them?

The information stored in a cookie varies depending on the site’s functions and goals. It may convey information about your browser’s settings, login details, personal preferences, and so on.

The following are some of the most common reasons why websites use cookies:

Personalizing your web browsing experience

Cookies can be used to track visitors’ browsing activities and preferences to improve the browsing experience.

Websites do this by using first-party cookies, which means that all cookies are created by the sites a user visits directly.

Most eCommerce sites use this type of cookie to monitor users’ shopping behaviors and preferences. Doing so enables them to keep track of users’ shopping carts and recommend products they might like.

User authentication and session management

Using cookies to collect login information can eliminate the need for users to log in every time they visit the same site.

Social media platforms and mobile banking solutions implement this practice by generating cookies containing a session ID each time a user logs in. 

A session ID consists of a unique static number for a specific duration of visit as proof of identity. The server will generate a new session ID when a user re-opens the browser or after a period of inactivity.  

This way, the web server can compare the session ID stored in the cookie to the one kept by the server to authenticate the login. 

Tracking your browsing behavior and activity

Business-wise, cookies are useful for crafting personalized marketing strategies. That can be done by tracking users’ browsing behavior and activities on the site.

By collecting information about age, gender, location, interests, and even browser information, eCommerce sites can build an accurate user profile and show the most relevant ads based on a user’s preferences.

Meanwhile, website analytics tools use cookies to monitor web traffic and user demographics. Webmasters can use the information to decide which strategies work best, boosting traffic and conversion rates.

Types of cookies

Here are several types of cookie you can use on your website:

• Session cookies ‒ also known as transient cookies, these are automatically deleted after the user closes their browser.
• Persistent cookies ‒ these carry an expiration date that determines when the browser can remove them.
• First-party cookies ‒ these are created by the website that visitors access directly.
• Third-party cookies ‒ these are created by third-party domains that are not visited directly by users.
• Secure cookies ‒ these can only be sent via a secure channel that enables HTTPS protocol.

Should you accept, clear, or disable cookies?

Under the General Data Protection Regulation (GDPR), websites must ask users for their consent to use cookies the first time they access a web page. This is done to protect sensitive data belonging to the user that the cookies may target.

That said, cookies are designed to only contain information that is given directly by users. 

You can choose to enable cookies when visiting websites to optimize your browsing experience. Cookies are especially useful in sites you frequently visit, as they can save you time by saving your preferred settings and content.

Since cookies remain unchanged when they travel between websites and browsers, they cannot carry viruses or malware. However, hackers can still tamper with them to access your browsing history.

You can set your cookie preferences via your browser’s settings. Chrome, for example, allows you to block third-party cookies and automatically delete all cookies when you quit the software.