The short answer
Data travels across the internet by being split into packets that route through networks of physical cables, routers and servers. The internet is stored in data centres worldwide connected by undersea and underground fibre-optic cables. When you enter a URL, your browser queries DNS servers to find the website's IP address, then requests and receives packets of webpage data.
The Physical Infrastructure of the Internet
The internet exists as a vast network of physical hardware spread across the globe. Data centres—large facilities filled with server racks—store websites, applications and services. These centres are connected by hundreds of thousands of miles of fibre-optic cables running beneath oceans, underground and along existing infrastructure like railway lines. Your home connection links to this network through cables (copper or fibre) or wireless signals that ultimately connect to a physical line.
No single entity owns or controls all of this infrastructure. Internet Service Providers, technology companies, governments and telecommunications firms each maintain portions of the network, which interconnect at exchange points where different networks meet and share traffic.
What Happens When You Type a URL
When you enter a web address into your browser, several steps occur in rapid succession:
- Your computer sends a query to a DNS (Domain Name System) server, which acts like a phone book for the internet, translating the human-readable domain name into a numerical IP address that identifies the destination server
- Your browser establishes a connection with that IP address using protocols that define how computers communicate
- Your browser sends an HTTP or HTTPS request asking for the specific webpage
- The server processes this request and prepares the response—HTML files, images, scripts and other resources
How Data Actually Travels
The information does not travel as a single continuous stream. Instead, it breaks into small units called packets, each typically containing between 1,000 and 1,500 bytes. Each packet carries a portion of your data plus addressing information that tells network equipment where it came from and where it needs to go.
These packets travel independently across the network, potentially taking different routes. Routers—specialized computers positioned throughout the internet—examine each packet's destination address and forward it along the most efficient available path. A single webpage request might involve packets passing through a dozen or more routers across different networks and countries.
When packets reach your computer, your operating system reassembles them in the correct order using sequence numbers embedded in each packet. If any packets arrive damaged or go missing, your computer requests retransmission of only those specific packets.
The Speed of Transmission
In fibre-optic cables, data travels as pulses of light at roughly two-thirds the speed of light in a vacuum. The actual speed you experience depends on the number of routers handling your packets, the distance to the destination server, and congestion along the route. This entire process—from typing a URL to seeing a webpage—typically completes in under a second for nearby servers, though international requests take longer due to the physical distance signals must travel.