You hear my voice on the radio or because of technology. Technology builds things, it advances civilizations, it lets you see and hear more than you ever could. You can have a conversation with someone on another continent, hear a concert in a different hemisphere, instantly.

But what sounds do we lose in the name of progress? Bernie Krause has been recording natural sounds for decades. His site wildsanctuary.com has over 3,500 hours of natural sounds. He says the sounds are getting more scarce.

"When I first started," Krause says, "I could record for 15 hours and get one hour of useable material. Now I have to record almost 2,000 hours to get an hour of usable material. From my perspective, technology has really impeded on natural sound and caused us not to hear it instead of to hear it. And it's one of the most serious problems when we go out and record. Aircraft of all kinds, private and commercial as well as motorcycles that you can hear seven or eight miles away. So that's technology to me."

Krause says nature has its own rhythm. White noise machines try to imitate nature but they don't quite get it right. "The replacement sounds are the sounds of human endeavor," he says, "and these are noises which are kind of random, and because they're random and have no real information in them that's useful to our survival, they really aren't very healthy at all."

Also in today's program, only about 10 percent of the population knows about Ctrl-F, the easy keyboard method of finding anything on a screen. I guess those that know about it figure everyone does. Those that don't would never think to ask. We talk to Alexis Madrigal of The Atlantic about this phenomenon.