If you are connecting to the Internet from home, you don't need a proxy server. In general, if you're not sure if you need a proxy server, you probably don't. One exception: sometimes organizations configure Internet Explorer to find the proxy server automatically by consulting a server in the IT department. In that case you could need a proxy server for Firefox or an audio/video player application, without knowing it. If you suspect this is the case, consult your local system administrator to find out what the correct proxy server settings are. Often Internet Explorer has been configured to pick this information up automatically from a server in your organization's IT department, but Firefox does not take advantage of that information.
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