Many schools, workplaces, and other organizations restrict internet access to increase productivity and discourage off-task browsing. While I don't recommend violating your organization's rules when it comes to web browsing, there may be times when you need to get around blocked sites. This article covers a few methods of how to get around blocked sites and bypass internet filters.
Proxy servers are servers that act as a gateway between a local network and the internet. Proxy servers can improve performance and security, and they can keep the machines behind them anonymous. This feature of proxy servers make them useful as tools to get around blocked sites. There are a ton of proxy servers on the internet for this purpose; a Google search should turn up about 5 million results. Many of these may be blocked by your filtering software, so it may take some trial and error before you find one that isn't. Since many filters will also block searches for proxy servers, you may have to do your searching on an unrestricted connection and write down the sites.
If you have permission to install applications, you can use Tor to get around blocked sites. Tor is a free anonymity software for web browsing that may be able to help you get around blocked sites by concealing your location and sending your web traffic through a network of virtual tunnels. Tor can be effective; but most organizations that restrict web usage also restrict install privileges.
However, even these restrictions can be bypassed by rebooting the computer form a different drive. This can be done by making a live CD or a bootable flash drive. A live CD is a CD-ROM that has an operating system installed on it. If you insert the disk and reboot the computer from the CD-ROM drive, you will go into this operating system rather than the one on the computer's hard drive. You can then use Tor to browse freely and get around blocked sites. A bootable flash drive is like a live CD, but uses a USB flash drive instead of a CD-ROM to get around blocked sites. For more information on this see the Tor Live CD FAQ.
Any of these methods can help you with how to get around blocked sites, but they are not guaranteed to work. As their use becomes more common, organizations will start to take preventative measure to halt their use. The best policy always to follow the rules and save your personal browsing for when you get home.