• Firefox will: Here you can set whether or not Firefox will your remember information about your web browsing like which sites you have visited, which files you have downloaded, what you have searched for, and whether or not you are logged into a website.
  • Set it to Remember history to remember information about your web browsing.
  • Set it to Never remember history for none of your browsing information to be remembered.
  • Set it to Use custom settings for history to pick and choose which information you want to be remembered.

• Automatically start Firefox in a private browsing session: Private Browsing is like temporarily switching to "Never remember history", while retaining your previous history. With this optionpreference enabled, Firefox will start in a private browsing session before turning off Private Browsing during the session. For more information, see Private Browsing.

• Remember my browsing history for at least ... days: Here you can specify how long you want Firefox to remember what pages you have visited. The default is 90 days.

• Remember download history: This optionpreference controls whether or not past downloads show up in the Downloads window. The Downloads window (accessible from Tools or by pressing CtrlCmd+J CtrlCmd+Y) displays a list of your recent downloads. Downloads optionspreferences are available in the Main panel.

• Remember search and form history: When you enter information in the search bar or web forms in Firefox, that information is saved so that Firefox can give suggestions when you enter information in forms in the future. To stop this behavior, uncheck this optionpreference. For more information, see Form autocomplete.

• Accept cookies from sites: A cookie is a file created by a website that stores information on your computer, such as site-specific preferences when visiting that site. By default cookies are enabled. Uncheck this optionpreference to disable the use of cookies. Note that some sites may not work properly when cookies are disabled. To control which sites may or may not set cookies, click the Exceptions... button.

• Accept third-party cookies: Unselecting this option will restrict cookie usage to the originating website only, meaning that no foreign cookies will be stored. See Disabling third party cookies.

• Keep until:
  • they expire: This is the default optionpreference. When set, this allows websites to specify how long a cookie will be stored by Firefox. This makes it possible for a site to remember your preferences and login information across browser sessions.
  • I close Firefox: With this optionpreference selected, Firefox will remove all stored cookies when closed.
  • ask me every time With this optionpreference enabled, Firefox will ask you how long you would like to keep a cookie (or refuse it entirely) every time a website attempts to set one.

To display the Cookie Manager click Show Cookies....

For more information on cookies, see the Cookies article.

• Clear history when Firefox closes: You can choose to have Firefox clear your history data when you close it. To configure what data is cleared, click the Settings... button. For details, read the Clear Recent History article.

Location Bar

• When using the location bar, suggest: The Location Bar is the horizontal bar that displays the web address. Here you can specify what kind of results show when you type in the Location bar. Select History and Bookmarks to have Firefox suggest results from your visited and bookmarked pages when you type in the location bar. Select History to use only visited pages and not bookmarks. Select Bookmarks to use only bookmarks and not visited pages. Select Nothing to turn off suggestions from the location bar.

• Keep my history for at least ... days: Here you can specify how long you want Firefox to remember what pages you have visited. The default is 90 days.

• Remember what I enter in forms and the search bar: When you enter information in web forms or the search bar in Firefox, that information is saved so that Firefox can give suggestions when you enter information in forms in the future. To stop this behavior, uncheck this optionpreference. For more information, see Form autocomplete.

• Remember what I've downloaded: This optionpreference controls whether or not past downloads show up in the Downloads window. The Downloads window (accessible from Tools or by pressing CtrlCmd+J CtrlCmd+Y) displays a list of your recent downloads. Downloads optionspreferences are available in the Main panel.

Cookies

A cookie is a file created by a website that stores information on your computer, such as site-specific preferences when visiting that site.

• Accept cookies from sites: By default cookies are enabled. Uncheck this optionpreference to disable the use of cookies. Note that some sites may not work properly when cookies are disabled.
• Accept third-party cookies: Unselecting this option will restrict cookie usage to the originating website only, meaning that no foreign cookies will be stored. To learn more about this, read about managing cookies.

• Keep until:
  • they expire: This is the default optionpreference. When set, this allows websites to specify how long a cookie will be stored by Firefox. This makes it possible for a site to remember your preferences and login information across browser sessions.
  • I close Firefox: With this optionpreference selected, Firefox will remove all stored cookies when closed.
  • ask me every time With this optionpreference enabled, Firefox will ask you how long you would like to keep a cookie (or refuse it entirely) every time a website attempts to set one.

To control which sites may or may not set cookies, click the Exceptions... button.

To display the Cookie Manager click Show Cookies....

Learn more about cookies, the individual optionspreferences, and how you can gain control over what sites are allowed to store cookies on your computer by reading about managing cookies.

Private Data

Private data is information Firefox stores about your web browsing, such as what sites you have visited, what files you have downloaded, what you have entered in search fields, and your passwords. For more information, see Clearing private data.

• Always clear my private data when I close Firefox: You can choose to have Firefox clear your private data when you close it. To configure what data is cleared, click the Settings... button.
• Ask me before clearing private data: With this optionpreference selected, Firefox will ask you before before automatically clearing the data specified by clicking Settings....

If you wish to clear your private data right now, you can click the Clear Now... button to do so. To clear your private data from outside the preferences dialog, either press CtrlCmd+Shift+Del or select Tools menu and select Clear Private Data....