Mirror site

Mirror websites or mirrors are replicas of other websites. The main purpose of mirrors is often reduced network traffic, improved access speed, or improved availability of the original site. Such websites have different URLs than the original, but host identical content to it. Mirrors can also serve as real-time backups.

Examples of websites with notable mirrors are KickassTorrents,The Pirate Bay, the website of the Environmental Protection Agency and .. Examples of websites where a part of the website is mirrored are free and open-source software projects such as GNU, in particular Linux distributions such as Debian and Fedora; such projects provide mirrors of the download sites (since those expected to have high load), but not do necessarily mirror the main websites.

There are known cases of mirror websites which attempt to gain sensitive information of or distribute malware to its users. Other types of malicious mirrors might attempt to make profit from the content of other websites, identify users or manipulate website contents.

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Wikipedia