Explainer: What Are U.S. Surveillance Programs Spying On?

The U.S. National Security Agency has made the telecom company Verizon hand over phone records.

Reports surfaced last week exposing secret U.S. government surveillance programs that gather, store, and analyze billions of domestic and foreign phone and Internet records. The information was leaked to the media by Edward Snowden, a 29-year-old American who worked as a contractor for the National Security Agency (NSA) and the CIA. U.S. officials say data gathering on such a large scale is instrumental in combating terrorism. Rights groups say it encroaches on civil liberties. RFE/RL looks at the main components of the surveillance programs.

The media reports based on the documents leaked by Snowden speak about the gathering of two different types of records -- phone records and Internet records. How has the information gathering allegedly been done?

In the case of phone records, the NSA obtained legal approval from a special U.S. court formed under the 1978 Foreign Intelligence Surveillance Act (FISA) to get the U.S. telecom company Verizon to hand over records of phone calls within, to, and from the United States.

The records consist of the date, length, and phone numbers involved in each call -- not of an actual recording of what was said, which would require a court warrant

In the case of Internet records, the NSA tapped directly into the servers of several online companies, including Facebook, Google, Microsoft, and Yahoo.

James Clapper, the U.S. director of national intelligence, said the data gathering was legal under FISA. The companies all deny that they knowingly allowed the government to access their servers.

The surveillance of Internet data has been reportedly done through a secret surveillance program codenamed PRISM. What is PRISM and how does it work?

PRISM allegedly monitors email, video and voice chat, videos, photos, voice-over IP conversations, file transfers, login notifications, and social-networking details. U.S. officials say PRISM allows the NSA and other agencies to track the communications of foreign nationals who are suspected of terrorism.

PRISM was first introduced in 2007 under changes to U.S. surveillance laws passed during the presidency of George W Bush after the September 11, 2001 terrorist attacks. It was renewed last year under President Barack Obama, and its existence was first revealed by the media last week.

PRISM is a data-collection program, and in this respect it differs substantially from the other powerful surveillance tool revealed to be used by the NSA, a program called Boundless Informant.

What is Boundless Informant?

Whereas PRISM deals with the collection of data, Boundless Informant organizes, indexes, and maps the records of communications, or metadata. According to information leaked to the British media, specialists in charge of Boundless Informant said that over a 30-day period in March almost 3 billion intelligence items had been gathered from U.S. computer networks alone. An additional 100 billion items came from abroad.

The program provides a color-coded world map based on how much intelligence the NSA is collecting from every country.

Which are the countries that are spied on the most, based on Boundless Informant?

U.S. arch-foe Iran tops the chart, accounting for more than 14 billion pieces of intelligence gathered in March, with two U.S. allies -- Pakistan and Jordan – coming a close second and third, respectively. They are followed by Egypt and India.

What kind of political reaction has the scandal prompted, both in the United States and abroad?

President Obama has defended the methods, saying they are an essential tool in counterterrorism. Obama also said the programs are legal and subject to congressional oversight. He assured Americans on June 7 that "nobody is listening to your telephone calls."

The reaction has been more vocal abroad. German Chancellor Angela Merkel has said she will raise the issue of the NSA's eavesdropping on European communications when she meets Obama in Berlin next week.

In Brussels, EU officials said they would also raise questions about the impact of such programs on the privacy of EU citizens at a trans-Atlantic meeting in Dublin on June 13.

In Britain, Foreign Secretary William Hague canceled a visit to Washington to address parliament on June 10. He denied allegations that the British surveillance agency GCHQ had used information provided by the United States to spy on British citizens, calling those claims "baseless."