You make a call from your land line or text a friend from your smartphone. You browse an online retailer for clothing, a book or music; you create a wish list or write a review.
You walk past a security camera outside your home; you use GPS to find your way to a business meeting. At the supermarket, you buy groceries with a credit card. Or you pay cash — but enter a loyalty card for the discount.
As you move through the ordinary activities of everyday life, you're leaving an electronic trail rich in data about your whereabouts, your interests and your relationships.
That's information of keen interest — and not only to marketers. As recent revelations about two National Security Agency surveillance programs show, at least some of those digital details are being collected and analyzed by the government.
President Barack Obama acknowledged Friday that the surveillance agency based at Fort Meade in Anne Arundel County has been collecting data on telephone calls made by U.S. citizens and monitoring the Internet and email use of foreigners as part of the nation's effort to combat terrorism.
Uproar over the two secret programs has sparked the latest round in the political and societal debate familiar to every American since the attacks on New York and Washington on Sept. 11, 2001: How far should the government reach into the lives of its citizens in the name of security?
What's new, however, is the vast proliferation of personal information now available for the taking. Facebook didn't exist when Congress passed the Patriot Act in 2001. And the first iPhone wasn't issued until more than five years later.
From 2002 to 2012, the number of wireless connections in the United States — including smartphones, tablets and other devices — more than doubled, from 141 million to 326 million, according to the industry group CTIA The Wireless Association.
Amy Webb, CEO of WebbMedia Group, a digital strategy consulting firm based in Baltimore, says the growth of technology and its incorporation into everyday life have outpaced the public's understanding of the privacy implications.
"We've got a whole bunch of people using these devices, and they're magical," said Webb. "But there are sacrifices that we make for that convenience. And one of those sacrifices is that our data is not totally locked down and reserved anymore just for us."
Obama said the telephone and Internet surveillance activities first detailed by the British newspaper The Guardian and The Washington Post were approved by the federal court that considers the legality of such surveillance and that Congress is briefed regularly. Lawmakers of both parties, including Rep. C.A. Dutch Ruppersberger of Baltimore County, the top Democrat on the House Intelligence Committee, have said such programs are needed to thwart terrorists.
Others raise privacy concerns. John Bacci, president of Foundation Financial Advisors in Linthicum, is a customer of Verizon, the telephone carrier named in a leaked order that for the first time documented that the NSA is collecting millions of phone records.
"It's another inch of ground we yield on the road to less freedom" in the name of security since the Sept. 11 attacks, Bacci said. "It seems like a million and one inches of ground. Suddenly, you have gone a long way."
James Hardesty, another Verizon customer, sees a trade-off.
"Anybody who doesn't think their phone calls haven't been monitored for the last 30 years has not read a spy novel," said Hardesty, chairman of Hardesty Capital Management in Baltimore.
He said the surveillance — in which the government collects details such as phone numbers and call duration but does not listen to the calls themselves — probably has prevented terrorism. He said he wouldn't lose any sleep over the NSA watching his phone activity.
"There are some bad people in the world," Hardesty said.
Michael Greenberger, founder and director of the Center for Health and Homeland Security at the University of Maryland, Baltimore, said the scope of NSA surveillance of what professionals call "telephony metadata" is likely to go far beyond what has been reported.
"I'm sure we are going to find out it's not just Verizon, it's everybody," he said. The program's disclosure, he predicted, "is going to be tough for the American people to digest."
"The initial reaction is one of great shock," he said. "Some people will say, 'If that can head off another Boston Marathon [bombing], then have at it.' "
The Guardian was the first to report the court order that requires Verizon to turn over records daily to the NSA.
The highly secretive NSA, which is fenced off from the rest of Fort Meade, collects and processes intelligence gathered from phone calls, Internet activity and other electronic communications. The number of employees at its steel-and-glass headquarters, visible from Route 32, is classified.
In a glossy brochure distributed to reporters last month for the groundbreaking of a computing center — an event actually held outside the NSA campus, away from where the center is to be built — the agency listed several "myths" about its operations.
An example: "MYTH: NSA monitors the world's communications systems at all times. REALITY: NSA is not an indiscriminate vacuum, collecting anything and everything. It performs its work with laser focus — and 'foreign' is the operative word."
Lawmakers confirmed the phone surveillance program last week and suggested that it involved more carriers and has continued for years.
James R. Clapper, the director of national intelligence, said the "unauthorized disclosure" of the order "threatens potentially long-lasting and irreversible harm to our ability to identify and respond to the many threats facing our nation."
Then he said he had directed that some details of the program be declassified "in order to provide a more thorough understanding" of what he called "a sensitive intelligence-collection operation."
The program does not allow the government to listen in on phone calls, view their content or learn the identities of individual subscribers, Clapper said. Rather, the target is metadata such as phone numbers dialed and length of calls.
"The collection is broad in scope because more narrow collection would limit our ability to screen for and identify terrorism-related communications," he said. "Acquiring this information allows us to make connections related to terrorist activities over time."
The Washington Post published details of a program called PRISM, through which it said the NSA taps into the central servers of Internet service providers, including Microsoft, Google, Facebook, Skype, YouTube and Apple, to extract "audio and video chats, photographs, emails, documents, and connection logs that enable analysts to track foreign targets."
Obama said the program does not apply to U.S. citizens or people living in the United States. Like the phone program, he said, the Foreign Intelligence Surveillance Court has authorized it and Congress is "fully apprised of it."
The president said there are trade-offs between "the need to keep the American people safe and our concerns about privacy" — and he welcomed the debate.
"It's important to recognize that you can't have 100 percent security and also then have 100 percent privacy and zero inconvenience," Obama said. "We're going to have to make some choices as a society. And what I can say is that in evaluating these programs, they make a difference in our capacity to anticipate and prevent possible terrorist activity. …
"The modest encroachments on the privacy that are involved in getting phone numbers or duration without a name attached and not looking at content ... it was worth us doing."
Wells C. Bennett, a fellow in national security law at the Brookings Institution and managing editor of the influential blog Lawfare, says it is difficult to assess the legality of such activities because while the law is public, the government's interpretation of the law, its application to the court and its arguments are not.
"The issue to my mind doesn't seem to be: Is the government breaking the law?" Bennett said. "It seems more like: What is their exact view, and if it's a continuing thing that just goes on and on, why shouldn't they be public more about it?"
Sen. Ben Cardin said Congress debated the Patriot Act — including the provision under which the court has granted the Verizon order — in public.
"Mass collection's mass collection," said the Maryland Democrat, who voted in favor of the Patriot Act in 2001 as a member of the House. "People didn't focus on it, but it was in the law. I don't think any of us are surprised, even though I wasn't aware of this until I saw it in the paper."
Still, Cardin said, "I think it's a valid question as to why they couldn't let people know that this was being done."
Rep. Donna Edwards, who voted against the most recent reauthorization of the Patriot Act, called for more transparency.
"The parameters of a program like this should be open to examination from members of Congress and the public," the Prince George's County Democrat said. "Everyone understands balancing national security and civil liberties, but we, the public, have to be the ones to say where the line is drawn."
Edwards said the country hasn't "struck quite the right balance" since Sept. 11.
"It's creep, creep, creep," she said. "You give up one thing until you give up another thing, and then you wake up one day and you don't have anything."
Webb, the digital strategist, said news that the government was mining data from private companies should not have come as a shock. It's the responsibility of users to understand that their actions leave digital footprints that can be observed by others, she added.
"If you really, really, really are concerned about your privacy and you don't want to participate in this ecosystem, then you need to move out to Western Maryland and live at the base of a cliff with a bag over your head," she said.
"If you're going to participate, you should understand what you're participating in."