How does nuget get automatic updates?

I find Nuget to be a very powerful tool with开发者_StackOverflow中文版 a lot of potential. However, I am confused, how does Nuget get updates for a package (e.g. ELMAH)? Is it looking at an ftp server for new downloads?

Thank

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NuGet looks a package sources to find updates. By default, it uses the official nuget feed (https://go.microsoft.com/fwlink/?LinkID=206669) to find updates. When package authors push new versions of packages to the feed, they are instantly available.