What are Web Cookies and How Do They Work?
By
Liz Fujiwara
•
Oct 21, 2025
Website cookies are small files that web browsers store on your device to improve your browsing experience. They track and remember your actions on websites, such as login information, items in a shopping cart, or your site preferences, allowing for faster, more personalized interactions. Beyond convenience, cookies also help website owners analyze traffic, improve functionality, and deliver targeted content or ads. In this article, we’ll dive into what cookies are, how they work, the benefits they offer, and the potential privacy and security risks you should be aware of.
Key Takeaways
Website cookies are small text files that enhance the user experience by storing data such as login credentials and preferences, facilitating session management and reducing server load.
Cookies can be categorized into different types, including session cookies, persistent cookies, first-party cookies, and third-party cookies, each serving unique roles in web browsing.
Privacy concerns surrounding cookies include potential identity theft and tracking risks, highlighting the importance of managing cookie settings and complying with regulations such as GDPR and CCPA.
What Are Website Cookies?
Website cookies are small text files created by websites and stored on a user’s device through web browsers. These files contain data that helps websites identify and remember users during their online sessions. Essentially, cookies act as a bridge between a user’s device and the website’s server, enabling a more personalized browsing experience.
The primary purpose of cookies is to improve a user’s online interaction. They store information such as login credentials, user preferences, and browsing activity, allowing websites to remember these details and provide a seamless experience. Without cookies, users would need to log in repeatedly on each page, and items in shopping carts could be lost upon leaving a site. This convenience is crucial for maintaining user engagement and satisfaction.
Cookies are also vital for session management, tracking, and personalizing user interactions with web applications. They allow websites to remember user activities during a session, such as keeping track of shopping cart items or maintaining session states. This functionality not only improves user experience but also reduces server load by storing less data on the server.
Types of Website Cookies
Understanding the different types of website cookies is essential for managing online privacy and improving user experience. Each type of cookie serves a specific purpose in web browsing.
Session cookies are temporary files that are deleted once the browser is closed. They store information about user activities during a particular browsing session, making navigation smoother and more efficient. For example, session cookies ensure that items added to a shopping cart remain there as the user browses different pages of an online store.
Persistent cookies, in contrast, remain on the user’s device until a specified expiration date or duration. These cookies enable websites to remember users and their preferences over longer periods, providing a more personalized experience. For instance, a persistent cookie can store login credentials so that users do not have to re-enter them each time they visit a website.
First-party cookies are created directly by the website a user is visiting, whereas third-party cookies come from domains different from the one shown in the address bar. Third-party cookies are often used for tracking and advertising, allowing advertisers to build user profiles based on browsing history and preferences. Understanding these distinctions is important for users who want to manage their online privacy effectively.
How Cookies Work
When a user visits a website, the process of setting cookies involves several steps:
The web server sends identifying data in the form of cookies to the browser.
The website’s server creates a text file containing this information when the user’s browser loads the site.
Cookies are set using the Set-Cookie header field in an HTTP response.
The browser stores the cookies on the user’s device.
Cookies can be categorized as follows:
First-party cookies: Created by the website being visited.
Third-party cookies: Generated by other domains.
Session cookies: Temporary and deleted after the browser is closed.
Persistent cookies: Remain on the device until their expiration date.
Cookies contain a unique session identifier that helps manage the user’s session and record items for virtual shopping carts. This includes essential cookies, computer cookies, internet cookies, user cookies, and existing cookies.
The main function of cookies in session management is to store information about user page activities, making website navigation easier. For instance, cookies can:
Remember which pages a user has visited, acting as bookmarks to enhance the browsing experience.
Store user data to enable websites to offer personalized content.
Facilitate targeted advertising, improving user engagement.
Cookies also help site owners reduce server load, as less data needs to be stored on the server. This efficiency allows quicker access to user-specific information, streamlining the overall web experience.
Benefits of Using Cookies
Cookies offer numerous benefits for both users and developers, making them an integral part of modern web browsing. One primary advantage is that cookies allow websites to remember users across sessions, improving convenience and streamlining tasks like logging in. For example, cookies store data associated with a unique ID, enabling personalized content delivery and enhancing the browsing experience.
Session management is another significant benefit of cookies. They ensure that items in shopping carts remain intact as users navigate different pages, preventing frustration and improving usability. This functionality is especially important for e-commerce websites, where maintaining session state is crucial for completing transactions.
Cookies also enable developers to personalize content and reduce server maintenance costs. By storing user preferences and login information, cookies tailor the browsing experience to individual needs. For instance, a website can remember a user’s language preference or display relevant content based on previous interactions.
Moreover, cookies store stateful information and track browsing data, helping developers optimize website functionalities and manage stored data. This tracking improves web browsing efficiency by allowing quicker access to a user’s browsing history and monitoring activity, making the overall experience more seamless and enjoyable.
Privacy Concerns and Security Issues
While cookies offer many benefits, they also pose significant privacy and security risks. On unencrypted networks, cookies can be exposed to attackers, potentially leading to identity theft and data breaches. For example, malicious actors can exploit cookies to steal user credentials and bypass security measures, putting sensitive information at risk.
Key concerns related to cookies include:
Attackers impersonating users by stealing cookies used as session identifiers, highlighting the importance of securing cookie data during transmission.
The creation of detailed user profiles through tracking, which presents privacy threats.
Third-party cookies compiling comprehensive user profiles, including sensitive information like gender and income, without user knowledge.
Cookies can also be misused as a form of spyware, collecting information without consent. Cross-site scripting (XSS) attacks may result in cookie theft via malicious HTML or JavaScript, further compromising privacy. These risks underscore the need for robust security measures to protect sensitive cookie information.
Examples of potential data breaches and identity theft highlight the seriousness of these concerns. Users should be proactive in safeguarding their online privacy by managing cookie settings, accessing information securely, and using encrypted networks.
Managing Cookies in Web Browsers
Managing cookies in web browsers is essential for maintaining online privacy and security. Users can effectively control their cookie settings by:
Regularly updating their browsers
Using browser plugins
Familiarizing themselves with the cookie management features in their browser settings, which allow for deleting, blocking, or modifying cookies
In Google Chrome, users can navigate the settings menu to adjust cookie preferences, including blocking third-party cookies in Incognito mode, balancing privacy with functionality. Mozilla Firefox offers a Privacy & Security section to manage cookies and improve tracking protection. Apple Safari allows users to prevent cross-site tracking and block all cookies via its preferences menu.
Microsoft Edge provides options to set tracking preferences and manage cookies through the privacy and site permissions menu. Opera enables users to allow or block cookies and site data in its privacy and security settings. Samsung Internet browser allows cookie adjustments through its app settings on mobile devices, offering options like allowing all cookies or blocking third-party cookies. When changes are made, the browser communicates the updated preferences to the server.
Disabling cookies can further increase privacy when sharing devices, preventing subsequent users from accessing prior browsing data. These practical steps empower users to maintain greater control over their online privacy and security.
Cookie Regulations and Compliance
Cookie regulations play a vital role in protecting consumer privacy and ensuring ethical data handling. Key points about the General Data Protection Regulation (GDPR) include:
Websites must obtain user consent before tracking users with cookies.
The regulation applies to any organization processing data of European Union residents, regardless of the organization’s location.
Organizations are required to provide clear information about the types of cookies used and their purposes.
In the United States, the California Consumer Privacy Act (CCPA) mandates that for-profit businesses provide consumers with rights regarding their personal data, including the ability to opt out of cookie tracking. The California Privacy Rights Act (CPRA) further amends the CCPA to enhance consumer privacy protections. Under both GDPR and CCPA, obtaining user consent for cookie storage and usage is a legal requirement.
Businesses must implement clear privacy and cookie policies to disclose data collection practices and secure user consent. These policies should specify the types of cookies used, their purposes, and instructions for managing preferences. Compliance with these regulations is essential for maintaining user trust and avoiding legal repercussions.
Fonzi: Revolutionizing AI Talent Acquisition
In the rapidly evolving world of technology, finding top-tier AI talent can be a daunting task. Fonzi addresses this challenge by revolutionizing AI talent acquisition with its innovative, curated approach. Fonzi is a specialized AI engineering talent marketplace that connects companies with pre-vetted AI engineers through its recurring hiring event, Match Day. Candidates benefit from a personalized experience, guided by dedicated Concierge Recruiters throughout the hiring journey.
Fonzi’s platform integrates seamlessly with existing recruitment tools, streamlining the hiring process and improving data accessibility. Unlike traditional job boards or black-box AI tools, Fonzi provides high-signal, structured evaluations with built-in fraud detection and bias auditing. This ensures both companies and candidates experience a fair and transparent hiring process.
By leveraging advanced technologies and a curated approach, Fonzi sets a new standard in AI talent acquisition. The platform enhances hiring efficiency while ensuring companies are matched with the best candidates, making it a game-changer in the recruitment industry.
How Fonzi Works
Fonzi operates through structured hiring events known as Match Day, where businesses connect with pre-vetted AI engineers. The marketplace includes:
AI-driven structured evaluations to assess candidates fairly and consistently
Live coding sessions
Comprehensive technical assessments
Key features of Fonzi include:
Recording and annotating interviews for transparent, detailed evaluation
AI-powered resume screening
Fraud detection in candidate applications
Bias-audited evaluations to enhance fairness and integrity
Fonzi makes hiring fast, consistent, and scalable, with most hires occurring within three weeks. This efficiency allows companies to fill critical AI roles quickly with highly qualified candidates.
Why Choose Fonzi for Hiring AI Engineers
Fonzi offers numerous advantages:
Significantly reduced time-to-hire, with most positions filled in under three weeks
Rapid candidate identification through AI streamlining the hiring process
High-quality hires, accepting only top-tier engineers and using bots to detect resume inconsistencies
Transparency, allowing candidates to choose companies they want to interview with after reviewing offers
Flexibility, supporting both early-stage startups and large enterprises with tailored solutions
Fonzi elevates the candidate experience by ensuring each candidate is matched to the right opportunity. This focus on engagement and satisfaction helps attract and retain top talent, making Fonzi a valuable partner in AI talent acquisition.
Summary
In summary, web cookies play a crucial role in enhancing online experiences by remembering user preferences, managing sessions, and delivering personalized content. However, they also carry privacy and security risks that users need to manage carefully. Proper cookie management in web browsers, along with compliance with regulations such as GDPR and CCPA, is essential for safeguarding online privacy.
Fonzi is transforming AI talent acquisition through its curated marketplace that connects companies with pre-vetted AI engineers. The platform’s structured evaluations, fraud detection, and bias auditing ensure a fair and efficient hiring process. By using Fonzi, companies can reduce time-to-hire, secure high-quality candidates, and provide an exceptional experience for both recruiters and candidates.
