What's this about the Government being shut down?

[jslvr4vr]

That it might shut down? What's going on?

http://www.washingtonpost.com/blogs/federal-eye/post/government-shutdown-2011-will-i-get-paid-what-will-be-open-what-can-i-expect/2011/04/06/AFfMK2oC_blog.html

I don't understand....did it happen before? Why?