In the beginning, the way phone calls were made was very similar to connecting a speaker to your home entertainment system and playing an old vinyl record. The microphone in the handset acted just like the needle on a record player, being vibrated by the sound of speaking rather than record grooves. The vibration converts to a tiny voltage and is amplified and sent out over wires to a speaker in the handset on the other side. The cost of the entire circuit included miles of copper wire and machines called “switches” at a central point to connect the wires on one side of the call to wires on the other side. In modern dollars, a single phone circuit used to cost thousands of dollars to physically construct.

With widespread adoption of the Internet, most places in the civilized world are already connected to each other, as if they were all in one giant building of rooms. The miles of copper are still there, but they are not wasted very often on carrying an analog audio stream that will fit perfectly into one third of one percent of a 20 megabit digital Internet connection. Now the old analog lines are being converted to carry the Internet itself. This already-connected world needs only to convert that audio voltage into a digital stream to take advantage of their existing Internet connection.

The expensive switches that once physically connected two sides of the circuit using very special hardware are no longer needed. The digitized audio can be directed to the intended destination by the same generic modern computing platforms that inexpensively provide just about every other Internet service. The result of these advancements is a drastic decrease in the expense of creating a now-virtual circuit between two parties. As a bonus, audio is not the only thing commonly digitized today. Video, document images, text, and other types of information can also be moved through this same virtual circuit.