A page on the Internet—whether it's full of words, images or both—doesn't come to you in one shipment. It's translated into digital information, chopped into pieces called packets, and sent to you like a puzzle that needs to be reassembled. Web pages are broken down this way because small pieces can travel faster and make the most efficient use of the Internet's resources. Instead of waiting while a long train of information goes by, packets can just fit in wherever and whenever there is space in a wire.
Each packet has its part of the data, plus additional information needs to be routed to the destination and reassembled with the rest of the packets. Reassembling is important because the packets do not necessarily arrive in the same order in which they were sent. Packets can get jumbled during transmission and occasionally even take different paths. Devices called router determine the most efficient path at the time the packets enter Internet traffic. This helps prevent traffic jams and makes the Internet more efficient. When the packets arrive at their destination, your computer discards the addressing information and puts the packets in the proper order to reassemble the information for you. Once all the packets are reassembled, the complete page appears on your computer screen.