What is #VoIP?
Google it, and you’ll get about 88,400,000 results.
Read the article page on Wikipedia, you will get 6899 words of explanation.
Watch this video, and 1 min and 41 secs are enough for you to understand.
Oh, but I think still need to type out its definition here:
Voice over Internet Protocol (VoIP), also called IP telephony, is a methodology and group of technologies for the delivery of voice communications and multimedia sessions over Internet Protocol (IP) networks, such as the Internet. The terms Internet telephony, broadband telephony, and broadband phone service specifically refer to the provisioning of communications services (voice, fax, SMS, voice-messaging) over the public Internet, rather than via the public switched telephone network (PSTN).
Honestly speaking, the definition makes me dizzier.
I am not going to write a thesis, so I chose the video.
What about you? Prefer to read or watch?