When you request a home page on the internet, a distant web server retrieves page content from its hard disk and through a highly complex process, chops the data into packets, and sprays them out into the global network. A single image can be composed of dozens of packets. Router devices on the network have tables or lists of where packets need to go, and determine the fastest route to send them. Each packet has information on where it came from and where it needs to go. Packets can take many possible paths.
Packets can arrive early, late or out of order.
Packets can collide. Packets can get lost. Imagine our demonstration happening millions of times a day for a single web site. The packets converge into the bottleneck of your modem and are passed on to your web browser. Your web browser stashes the packets as completed images, text, sounds, or other data in a folder called the cache.