# How Do Two Clocks Agree?
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Your watch and your laptop both say 3:00 PM. They've never communicated. How?
These posts are AI-assisted and written as a personal learning exercise. They may contain errors and shouldn't be treated as authoritative sources.
Your watch and your laptop both say 3:00 PM. They've never communicated. How?
You flip a switch. Photons stream from a wire, cross the room, enter your eyes, and become seeing. Every step is the same force.
You click a button. A name appears. 200 milliseconds. Behind that click: DNS, TCP, TLS, HTTP, a load balancer, a connection pool, a database query, and every layer in reverse.