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# Using Privacy Features

Your browser includes features you can use to enhance the privacy and security of your personal information. The sections that follow describe how your browser can help you control cookies, passwords, forms, and images while you are surfing the Internet.

Some web sites publish their privacy policies according to the Platform for Privacy Preferences (P3P) standard. For information on how to customize your browser based on this standard, see Setting Privacy Levels.

For information about related &brandShortName; security features, see Signing & Encrypting Messages and Using Certificates.

For general information about privacy and security, see the online documents:

- Virus protection
- Online shopping (and Banking)
- Children and the Internet

Privacy topics:

- Privacy on the Internet
- Using the Cookie Manager
- Using the Password Manager
- Using the Form Manager
- Encrypting Stored Sensitive Information
- Managing Images
- Privacy & Security Preferences

# Privacy on the Internet

This section summarizes some background information about privacy on the Internet. It also describes several things you can do to help safeguard your own privacy. It is not intended to provide a complete description of Internet privacy issues.

In this section:

- What Information Does My Browser Give to a Web Site?
- What Are Cookies, and How Do They Work?
- How Can I Control Web Pages in Email Messages?
- How Can I Make Sure Unauthorized People Don't Use Information About Me?

## What Information Does My Browser Give to a Web Site?

When your browser displays a web page—for example, each time you click a link or type a URL, or when a web page is displayed in an email message—it gives certain kinds of information to the site. This information may include (but is not limited to) your operating environment, your Internet address, and the page you're coming from.

### Operating Environment

The site is told something about your operating environment, such as your browser type and operating system. This helps the site present the page in the best way for your screen. For example, the site might learn that you use the French version of Mozilla 1.2 on a Windows 2000 computer.

### Internet Address

Your browser must tell the site your Internet address (also known as the Internet Protocol, or IP address) so the site knows where to send the page you are requesting. The site can't present the page you want to see unless it knows your IP address.

Your IP address can be either temporary or fixed (static).

If you connect to the Internet through a standard modem that's attached to your phone line, then your Internet service provider (ISP) may assign you a temporary IP address each time you log on. You use the temporary IP address for the duration of your Internet session—for example, until you sign off or hang up your dial-up connection, or otherwise end your computer's live connection with the Internet. Each ISP has many IP addresses, and they assign the addresses at random to users.

If you have DSL, a cable modem, or a fiber-optic connection, you may have a fixed IP address that you use every time you connect.

Your IP address is not the same as your email address.

### Referring Page

The site is also told which page you were reading when you clicked a link to see one of the site's pages. This allows the site to know which site referred you. Or, as you traverse the site, it allows the site to know which of its pages you came from.

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## What Are Cookies, and How Do They Work?

A cookie is a small bit of information used by some web sites. When you visit a site that uses cookies, the site might ask your browser to place one or more cookies on your hard disk.

Later, when you return to the site, your browser sends back the cookies that belong to the site.

When you are using the default cookie settings, this activity is invisible to you, and you won't know when a site is setting a cookie or when your browser is sending a web site's cookie back. However, you can set your preferences so that you will be asked before a cookie is set. For information on how to do this, see Setting Privacy Levels.

### How Do Sites Use Cookie Information?

Cookies allow a site to know something about your previous visits. For example, if you typically search for local weather or purchase books at a web site, the site may use cookies to remember what city you live in or what authors you like, so it can make your next visit easier and more useful.

Many web sites publish privacy policies that describe how they use the information they receive.

You can check a web site's privacy policy to see what it says about the information it collects, how that information is used, and what choices you have regarding the use of that information. To learn how to do this, see Viewing Privacy Policies.

For information on how to manage cookies with the aid of published privacy policies, see Setting Privacy Levels.

### What Are Third-Party Cookies?

If your browser stores a site's cookie, it will return the cookie only to that particular site. Your browser will not provide one site with cookies set by another. Since a web site can only receive its own cookies, it can learn about your activities while you are at that site but not your activities in general while surfing the Web.

But sometimes a web site displays content that is hosted on another web site. That content can be anything from an image to text or an advertisement. The other web site that hosts such elements also has the ability to store a cookie in your browser, even though you don't visit the site directly.

Cookies that are stored by a site other than the one you are visiting are called third-party cookies or foreign cookies. Web sites sometimes use third-party cookies with transparent GIFs, which are special images that help sites count users, track email responses, learn more about how visitors use the site, or customize your browsing experience. (Transparent GIFs are also known as web beacons or web bugs.)

If you want, you can adjust your cookie preferences so that sites can store ordinary cookies but not third-party ones.

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## How Can I Control Web Pages in Email Messages?

You can disable cookies, images, JavaScript, and plug-ins completely for web pages that are received as part of email messages.

While it may be convenient to enable some or all of these capabilities when you're browsing the web, they may not be necessary in single web pages sent as attachments to messages.

For information on enabling or disabling cookies, images, JavaScript, and plug-ins in email messages, see the following sections:

- Privacy & Security Preferences - Cookies
- Mail & Newsgroups Preferences - Message Display
- Advanced Preferences - Scripts & Plug-ins

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## How Can I Make Sure Unauthorized People Don't Use Information About Me?

The best way to keep your information private is to read the privacy policies for the web sites you visit and the Internet services you use, and to be cautious about giving out your personal information online.

The Internet is a public network. When you send your name, phone number, address, and other personal information over the network (via a web page, email, or any other method), it is possible that someone else may be able to intercept it.

Here are some questions you might ask about a web site's privacy policy:

- What kinds of personal information is this site gathering?
- How will the site use the information?
- Will the site share the information with others and do I have choices regarding the use of any shared information?
- Can I access some or all of the information a site gathers about me, in order to inspect or update it?
- How does the site protect the information?
- How do I contact the web site if I have questions or problems?

For information about checking a web site's privacy policy, see Viewing Privacy Policies.

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