VoIP software says that it makes phone calls over the internet. But using Skype and Google Voice, calls can be made to landlines and mobile phones. What are these services termed as? What is the name for the technology that permits this?
Both Google Voice and Skype Out, and similar services, are still VOIP.
Your voice gets digitized and "carried" from your computer over the internet, until it reaches a gateway server that knows how to contact a phone number and de-digitize the info back into voice etc. But your voice is definitely making its way over IP to get to its destination (as well as the voice of whomever you're talking to).