WebRTC

 WebRTC  is a W3C Candidate Recommendation that defines a set of JS APIs for Real-Time Communications (RTC) capabilities, supported by modern browsers, and some video chat sites, sometimes used for remote participation during IndieWebCamps and virtual Homebrew Website Club meetups.



Services
The following sites support in-browser to browser video-chat using WebRTC:
 * https://talky.io/
 * https://appear.in/
 * Vidyo

Articles

 * 2014-10-16 GigaOM: Hello Firefox! Mozilla’s browser gets built-in WebRTC video chat through Telefónica partnership
 * About the former Firefox Hello