In Firefox browser: In the top right corner of the Firefox browser window, click Open menu (three horizontal bars) and select Options. Then select the Privacy tab. Select an option from the drop-down menu in History section: Firefox: will use user's settings. Check Accept Cookies to enable, uncheck to disable cookies. Select the storage period for cookies: Store: until they expire — the cookie will be deleted when the expiry date is reached, which is set by the site sending the cookie. Store: until you close Firefox — cookies stored on your computer will be deleted when you close Firefox. Store: ask every time — every time a website tries to send a cookie, the browser will prompt you to decide whether to store the cookie. Close the options window to save your settings More information about Firefox Settings.
In Google Chrome: In the top right-hand corner of the Google Chrome browser address bar, select Customize and Control Google Chrome (three horizontal lines) Select Settings. Go down the window and click Show advanced settings... In the Privacy section, click Content Settings. In the Cookies section you can change the following cookie settings: Block attempts to place data from third-party websites on your computer Block cookies and data from third-party websites — check the Ignore exceptions and block the creation of third-party cookies. Remember that this setting prevents most pages that require you to log in from working. Learn more about Google Chrome Settings.
In Internet Explorer 9 In the browser window, click Tools and then select Internet Options. Click the Privacy tab, then under Settings, move the slider to the highest position to block all cookies, or to the lowest position to allow all cookies, and then click OK. Learn more about Internet Explorer Settings.
In Safari Changing your cookie preferences or deleting cookies and site data in Safari may affect the performance of other programs, such as the Dashboard. Select Menu Safari > Preferences, click Privacy, and do any of the following: Changing the way you accept cookies and site data: Select one of the options next to the Cookies and Site Data label: Always block: Safari does not allow websites, third parties, or advertisers to store cookies or other data on your Mac. This may prevent some sites from working properly. Only from the current site: Safari only accepts cookies and site data from the currently displayed site. Websites often contain embedded elements from other sources. Safari does not allow these other parties to store or access cookies or other data. From the sites you visited: Safari only accepts cookies and site data from those sites that you visit. Safari uses existing cookies to determine whether you have visited the site before. Checking this checkbox helps prevent sites that contain embedded material from other sites from storing cookies and other data on your Mac. Always allow: Safari allows all websites, other entities and advertisers to store cookies and other data on your Mac. Learn more about managing cookies and website data in Safari 8 (Yosemite) Blocking cookies in Safari on your iPhone, iPad, or iPod touch
In Opera Cookie settings Settings > Preferences > Advanced > Cookies Cookie settings allow you to control how cookies are handled. By default, all cookies are accepted. The following options are available in the Opera browser: Accept cookies — all cookies are accepted (option set by default). Only accept cookies from the website you are visiting — all cookies from domains other than the domain you are visiting are rejected. Never accept cookies — all cookies are rejected. More information about cookies in Opera.