EchoLink® software allows licensed Amateur Radio stations to communicate with one another over the Internet, using streaming-audio technology. The program allows worldwide connections to be made between stations, or from computer to station, greatly enhancing Amateur Radio's communications capabilities. There are more than 350,000 validated users worldwide - in 159 of the world's 193 nations - with about 6,000 online at any given time.

https://www.echolink.org/