RTR18YWCREUTERS/Jason Reed
The National Security Agency collects the cellular telephone data for millions of unsuspecting Americans every day, according to a Top Secret court order obtained by the Guardian.

Verizon is required to provide the secret intelligence agency with all call detail records " on an ongoing daily basis" until the order expires July 19.

But what exactly is this agency? Who leads it? And what is their mission?

It's your turn to learn.

Their headquarters is in a sprawling complex in Fort Meade, Maryland, just outside of Washington.

National Security Agency

The NSA was founded in 1952. Until 1977, they operated from Arlington Hall, a former girls school in Arlington, Virginia.

National Security Agency

The actual current size of the NSA is classified. It's square footage is roughly the same size as the Pentagon, and it has 112 acres of parking spaces.

National Security Agency

The mission of the NSA is to acquire and analyze information in an effort to identify threats to U.S. interests, and to protect America's information.

REUTERS/Jason Reed

Four-Star Army Gen. Keith Alexander heads the NSA. His actual title is Commander, U.S. Cyber Command; Director, National Security Agency; and Chief, Central Security Service.

National Security Agency

The operations inside the walls of the NSA are so secret, it's jokingly referred to as "No Such Agency" or "Never Say Anything."

National Security Agency

But when President Obama receives his daily intelligence briefing, it's estimated that as much as 75% of the information comes from the NSA.

REUTERS/Jason Reed

Every day, the NSA intercepts and stores billions of emails, phone calls, and other forms of communication.

REUTERS/Jason Reed

Last month, it was revealed that NSA hackers harvest 2.1 million gigabytes of data per hour.

AP Photo
National Security Agency

U.S. service members have given their lives in secret missions associated with the NSA. This memorial at the agency's headquarters honors those who "served in silence."

National Security Agency

Now see how the NSA fits into the complex American intelligence system

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