1 / 20

What are Cookies?

Learn about cookies, small pieces of data stored on your device by websites, enabling them to remember your preferences and track your online activities. Understand how cookies work, their controversy, and importance in personalized online experiences.

ltheodore
Download Presentation

What are Cookies?

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. What are Cookies? Cookies

  2. How did they do that? Cookies

  3. Sites that know you... • Just a few common examples: • my.yahoo.com • www.amazon.com • Each time I return to these sites, they remember who I am. • Yahoo remembers my news, bookmarks, etc. • Amazon.com remembers what books I have browsed and makes recommendations. • How do they do that? Cookies

  4. What is a Cookie? • Small piece of data generated by a web server, stored on the client’s hard drive. • Controversial, as it enables web sites to track web users and their habits (more later…) Cookies

  5. Tracking Unique Visitors • Step 1: Person A requests home page for amazon.com • Step 2: amazon.com Web Server generates a new unique ID. • Step 3: Server returns home page plus a cookie set to the unique ID. • Step 4: Each time Person A returns to amazon.com, the browser automatically sends the cookie along with web page requested. Cookies

  6. Cookie Conversation Give me the home page! Browser Server Here’s the home page plus a cookie. Now, give me the news page (cookie is sent automatically) I’ve seen you before… Here’s the news page. Cookies

  7. Cookie Notes • Created in 1994 for Netscape 1.1 • Cookies cannot be larger than 4K • No domain (netscape.com, microsoft.com) can have more than 20 cookies. • Cookies stay on your machine until: • they automatically expire • they are explicitly deleted • Cookies work the same on all browsers. No cross-browser problems here! Cookies

  8. Magical Cookies • The term cookie comes from an old programming hack, called Magical Cookies. • If a programmer couldn’t make two parts of a program communicate, she would create a “magical cookie”, a small text file containing data to transfer between program parts. Cookies

  9. Why use Cookies? • Tracking unique visitors • Creating personalized web sites • Shopping Carts • Tracking users across your site: • e.g. do users that visit your sports news page also visit your sports store? Cookies

  10. Cookie Anatomy Cookies

  11. Cookie Anatomy • Version 0 specifies six cookie parts: • Name • Domain • Path • Expires • Secure Cookies

  12. Managing Cookies Cookies

  13. In Netscape 4.0 and above • Netscape provides several cookie options • Accept all cookies • Accept only cookies that get sent back to the originating server (used to block third party ads) • Disable cookies • Warn me before accepting a cookie. • Menu Tab: Edit -> Preferences -> Advanced Cookies

  14. Cookies

  15. In Internet Explorer • Provides several options: • Prompt before accepting cookies • Disable all cookie use • Always accept cookies • IE 5.0: • Menu: Tools -> Internet Options -> Security -> Custom Level Cookies

  16. Cookies

  17. Netscape Cookie Files • Netscape stores all cookies within a cookies.txt file. • Columns: • Domain name • HTTP Header: • TRUE: cookie was set by an HTTP header • FALSE: cookie was set by JavaScript • Path • Secure • Name • Value • Let’s take a look... Cookies

  18. IE Cookie Files • Cookie files are stored within a cookies directory under windows: C:\windows\cookies • Each cookie gets its own name. • Let’s take a look... Cookies

  19. Cookie Block Software • Cookie Central has pointers to lots of cookie blocking software. • Cookie Pal • Cookie Crusher • Cookie Cruncher • etc. Cookies

  20. Privacy • Lets look at this website that provide informmation such as address, phone, email, and more: • www.411.com • Yahoo: • http://people.yahoo.com/ • http://find.intelius.com/search-name.php?ReportType=8& Cookies

More Related