Federal authorities have shut down Megaupload, one of the world's largest file-sharing services. The move came just a day after last week's mass online protest against two controversial pieces of anti-piracy legislation — the House's Stop Online Piracy Act and the Senate's Protect Intellectual Property Act. If the FBI can take down a massive site like Megaupload, is file-sharing doomed even without stronger anti-piracy laws? Here, a brief guide:

What is — or was — Megaupload?
It was "what's known as a file locker," says Dwight Silverman at the Houston Chronicle. The site allowed its users to upload anything from a text file to a full-length feature film, then share a link to the file with anyone interested in seeing it. It was a huge operation, officially registered in Hong Kong, but with servers in Ashburn, Va., and Washington, D.C., as well as the Netherlands and Canada. The FBI said Megaupload cost copyright holders more than $500 million in lost income by letting the site's 150 million registered users illegally download copyrighted content for free. According to the indictment, Megaupload raked in $175 million in 2010 from ads and premium subscriptions.

How did the government put a stop to it?
FBI agents forcibly shut the site down based on an order issued by a U.S. District Court. Visitors to the site now just see a notice saying that the site has been seized, and they can't access any content. The feds also arrested four people, including Megaupload founder Kim Dotcom. (He was born Kim Schmitz, but changed his name in honor of the business that made him rich). A citizen of both Finland and Germany, he lived in Hong Kong and New Zealand, where he was nabbed with the help of local authorities.

What does Megaupload say for itself?
The company insists the charges are "grotesquely overblown." "The fact is that the vast majority of Mega's internet traffic is legitimate," the company said in a statement, "and we are here to stay." The site's fans certainly aren't taking the crackdown lying down: After the arrests, the Department of Justice's website suffered a cyber attack blamed on the hacktivist group Anonymous. And Megaupload has received endorsements from powerful recording artists, including Kanye West, Will.i.am, and Alicia Keys.

Does this mean we don't need stronger anti-piracy laws?
Some are making that argument. If the U.S. government already has the power to shut down a gigantic overseas file-sharing service like Megaupload, says Timothy B. Lee at Ars Technica, why do we need more muscular anti-piracy laws? Well, the feds made an example of Megaupload, but they didn't stop illegal file-sharing, says Darren Franich at Entertainment Weekly. There will always be "savvy foreigners" ready and able to "use the tangled web of international copyright laws" to put up the next great file-sharing site.

Sources: Ars Technica, Digital Trends, EW, Houston Chronicle, Torrent Freak