How Does Wi-Fi Know Which Device to Send Data To?

Imagine your Wi-Fi router is a teacher in a classroom full of students (your devices). When the teacher wants to show a picture, she doesn't just shout it out. She writes each student's name on a small piece of paper and hands it to them specifically.

Your TV, phone, and laptop all have unique names called MAC addresses. These are like digital fingerprints that never change. When you press play on Netflix on your TV, the router looks at the request and says, 'Ah! This picture is for the student sitting in the blue chair.' It then wraps the data in a little envelope with the TV's name written clearly on the front.

If the router sent every piece of data to everyone, it would get messy. So, it uses a trick called beamforming. Instead of sending radio waves in all directions like a lightbulb, your modern router can focus the signal like a laser pointer directly at your TV. This makes the connection faster and uses less energy.