Video cameras continue to gain widespread use, but there are privacy and environmental limitations in how well they work. Acoustical waves are an alternative medium that may bypass those limitations.

Breakthroughs, discoveries, and DIY tips sent six days a week. Terms of Service and Privacy Policy. We live our entire lives surrounded by them. They slam into us ...

When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. What if you could listen to music or a podcast without headphones or earbuds and without ...