How Your Phone's GPS Works Without Internet?

Your phone’s GPS works like a special map that talks to satellites floating high above us.

Imagine your phone is like a little detective who can talk to satellites in space. These satellites send out messages, and your phone listens for them. Even without the internet, it can still figure out where you are by measuring how long it takes for those messages to reach you.

Each satellite sends a message with a special time stamp. Your phone checks the time it receives that message and compares it to the time it was sent. Because light (and radio waves) travel at a steady speed, your phone can tell how far away the satellite is from it, like counting seconds between when you see a lightning flash and hear the thunder.

Your phone does this with messages from at least four satellites. By knowing how far it is from each one, it can pinpoint exactly where you are on Earth, just like solving a puzzle with clues from different directions!