Some web browsers let you block and unblock a website or a list of websites. Below are example of browsers that can block or allow websites through a managed list:
Internet Explorer includes a Content Advisor tool that lets you control the types of content that a user may view or access on the Internet. The Content Advisor tool is disabled by default and you can enable it from Internet Options. To open Internet Options, type inetcpl.cpl in the run command in Windows or open it via the Internet Explorer tools menu or from the Control Panel in Windows. Click the Content Advisor tab and then click the “Enable” button to start using and managing the settings for the tool.

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Mozilla Firefox does not include a built-in Content Advisor, but you can install a third-party extension to block websites. Examples of such add-ons are BlockSite, ProCon Latte and FoxFilter.
There’s no option to block a website within Google Chrome but you may install the SiteBlock extension in the Chrome browser.

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You can block or unblock websites in the Opera browser by entering the URL or IP address via the Blocked Content option. Navigate through to Tools > Preferences > Content. Click on “Blocked Content” and then click the “Add” button. Enter the URL or IP address to block it.

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