Flash Cookie


A Flash Cookie, also known as a Local Shared Object (LSO), is a small data file stored on a user’s computer by Adobe Flash Player. It is used to save user preferences, track website activity, and manage multimedia content within Flash applications. Flash Cookies operate similarly to standard cookies but are managed separately because they are stored in a different location on the user’s device.


The phonetic spelling of “Flash Cookie” is: /ˈflæʃ ˈkʊk.i/

Key Takeaways

  1. Flash cookies, also known as Local Shared Objects (LSOs), are similar to regular cookies but are stored by Adobe Flash Player, which enables the storage of more sophisticated data to enhance user experience.
  2. Unlike regular cookies, flash cookies are not easily managed through browser settings, making them more difficult to control and posing a potential privacy risk as they can track user behavior without their knowledge.
  3. As Flash has been discontinued by Adobe, Flash cookies are becoming less common, and new privacy regulations have made their use more controlled and transparent, with most websites no longer relying on them for storing user data.


The term “Flash Cookie” is significant in the realm of technology because it refers to a specific type of tracking and storage mechanism, officially known as Local Shared Objects (LSOs), employed by Adobe Flash Player to store user preferences, settings, and usage data.

These cookies function similarly to regular HTTP cookies in ensuring a more personalized and convenient browsing experience, such as saving login credentials and customizing website interfaces.

However, their importance is further underscored by the fact that they are harder to detect and delete than regular HTTP cookies, potentially leading to privacy concerns and unauthorized monitoring of user activities.

As a result, understanding the concept of Flash Cookies is vital for both users who wish to maintain control of their personal information and developers who aim to create transparent and ethical web applications.


Flash cookies, also known as Local Shared Objects (LSOs), serve a significant role in enhancing a user’s experience on websites that utilize Adobe Flash technology. The primary purpose of Flash cookies is to store user preferences, settings, and data on local devices for various Flash applications, essentially enabling multimedia-rich websites to maintain consistency and reliability when revisited by the user.

By doing so, Flash cookies contribute to a seamless browsing experience, as they allow Flash-based websites to recall user data, saved games, volume preferences, and other customizable elements more efficiently. Additionally, they help in maintaining consistency across multiple devices for synchronized data retrieval.

Another notable purpose of Flash cookies is that they assist advertisers and marketers in tracking and analyzing user behavior while interacting online, enabling them to deliver more personalized and targeted advertising content. Flash cookies can provide more accurate and precise analytics compared to traditional cookie methods, as they can store more data and are not typically removed by standard browser cleaning methods.

Consequently, Flash cookies have faced criticism and concerns regarding privacy and user tracking. Despite their decline in popularity and widespread adoption of HTML5, Flash cookies are still utilized by some websites and remain an important aspect of understanding user experience and online advertising practices.

Examples of Flash Cookie

Flash cookies, also known as Local Shared Objects (LSOs), are small files stored on a user’s computer by websites that run Adobe Flash. They are used to store user preferences, track user behavior, and enable certain features on websites. Here are three real-world examples of Flash cookie usage:

Flash-based online games:Many online games that use Adobe Flash employ Flash cookies to store a user’s gameplay data, like the progress, high scores, user preferences (such as music or sound effect levels), and in-game currency. For instance, popular Flash game websites like Kongregate or Newgrounds utilize Flash cookies to improve user experience and remember settings across sessions.

Web-based video players:Video streaming websites, such as the early versions of YouTube and Vimeo, used Flash cookies to store the user’s playback preferences, like volume settings and preferred video resolution. These cookies enabled the video player to preserve user preferences across sessions and provided a more customized viewing experience.

Online advertising and analytics:Advertisers and marketers often use Flash cookies to track user behavior across multiple websites and gather data about user preferences. This information helps them deliver more targeted advertisements, conduct market research, and improve website functionality. For example, an advertising company might use Flash cookies to monitor which products a user views on different e-commerce sites, and then serve personalized ads based on this browsing history.

Flash Cookie FAQ

What is a Flash Cookie?

A Flash Cookie, also known as a Local Shared Object (LSO), is a small data file created by Adobe Flash that is stored on your computer. It is similar to a regular cookie used by websites to save information about your preferences, settings, and browsing history. However, Flash Cookies are typically used for Flash-based websites and multimedia content.

How do Flash Cookies differ from regular HTTP Cookies?

Although Flash Cookies serve a similar purpose as HTTP cookies, there are several key differences. Firstly, Flash Cookies are typically larger in size and can store more information. Secondly, they can persist even after clearing a browser’s cache and cookies, making them more difficult to remove. Lastly, Flash Cookies are managed separately from browser settings, and users must use Adobe’s settings panel to control their Flash Cookies.

Are Flash Cookies a privacy concern?

Yes, Flash Cookies can pose privacy concerns as they have the capability to track your online activities, even after being deleted. This is because they can be stored in locations separate from regular cookies. Some websites might use Flash Cookies to identify and track users without their consent, violating user privacy.

How can I manage or delete Flash Cookies on my computer?

To manage or delete Flash Cookies, you will need to access the Adobe Flash Player settings. To do this, right-click on any Flash content in your browser, select “Settings,” and navigate to the “Local Storage” tab. Here, you can set limits on storage or delete Flash Cookies for specific websites. Alternatively, you can visit Adobe’s website to access the Global Storage Settings Panel and manage your Flash Cookie settings.

How can I prevent Flash Cookies from being stored on my computer?

To prevent Flash Cookies from being stored on your computer, navigate to the Adobe Flash Player settings by right-clicking on any Flash content and selecting “Settings.” In the “Local Storage” tab, move the slider to “None” to disallow any Flash Cookie storage. Additionally, you can uncheck the box next to “Allow third-party Flash content to store data on your computer” to further protect your privacy.

Related Technology Terms

  • Local Shared Object (LSO)
  • Browser Storage
  • Adobe Flash Player
  • Privacy Settings
  • Cookie Management

Sources for More Information


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