1. The first famous phrase spoken on a phone was an emergency call. On March 10, 1876, inventor Alexander Graham Bell made the world's very first successful telephone call to his assistant in the next room, saying: "Mr. Watson, come here—I want to see you!" after accidentally spilling battery acid on his clothes!

2. Telephones convert your voice into electrical waves. When you speak into a phone, a tiny microphone converts the sound waves of your voice into electrical signals (or pulses of light). These signals travel rapidly across wires or radio waves to the receiving phone, where a speaker converts them right back into sound!

3. The first mobile phone was nicknamed "The Brick." In 1973, Motorola engineer Martin Cooper made the first wireless mobile phone call on a device called the DynaTAC 8000X. It weighed over 2 pounds, was as big as a real brick, took 10 hours to charge, and only provided 30 minutes of talk time!

4. Old phones didn't need to be plugged into wall outlets for power. Traditional landline telephones drew their power directly from the copper telephone wires running along utility poles outside. Because of this, home landline phones kept working even during massive electrical power outages!

5. Smartphones carry millions of times more computing power than NASA used to land on the Moon. The Apollo 11 guidance computer that landed astronauts on the Moon in 1969 had a tiny fraction of the memory and processing power found inside a standard modern smartphone today!

6. Cellular networks are named after overlapping hexagonal "cells." Mobile phones are called "cell phones" because geography is divided into thousands of small, overlapping geographic zones called cells. Each cell has its own radio tower that seamlessly handoffs your call to the next tower as you travel in a moving car!

7. Fiber-optic phone cables send your voice using laser beams. Today, billions of phone calls and internet messages travel through fiber-optic cables—thin strands of pure glass as fine as human hair. Instead of electricity, information shoots through the glass as pulses of laser light bouncing off internal walls at nearly the speed of light!