Explain · analogy · Like I'm five version
How Wi-Fi works in terms of a postman who never walks
Wi-Fi is like a postman who stays in one spot and throws letters through the air to your tablet.
The router is a very busy postman sitting in your hallway. He does not wear a uniform, but he does have many glowing lights that blink like tiny disco balls. Instead of walking to your front door, he turns your photos and games into invisible, wiggly waves. He tosses these waves across the room as fast as a racing car to get your cartoons on the screen.
When you tap your screen, your tablet sends a quick message back to the postman to say hello. The postman catches this message and knows exactly what you want to see next. If you walk too far into the garden, the postman cannot reach you with his invisible balls of data. He stays stuck in the hall, so your video might get a bit grumpy and stop moving for a second.
Everything happens so quickly that you never see the postman work. He is always busy, even when you are asleep and the house is quiet. He does not need a bicycle or a letterbox, but he does need a plug in the wall to keep his energy up. He is the smallest, fastest postman in the whole world, and he never once asks for a cup of tea.
Where the analogy breaks downThe postman does not actually carry letters, but instead transmits binary code using radio frequencies.