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The Internet is a packet-switched network, which means that when you send information across the Internet from your computer to another computer, the data is broken into small packets. A series of switches called routers sends each packet across the Net individually. After all the packets arrive at the receiving computer, they are recombined into their original, unified form. Two protocols do the work of breaking the data into packets, routing the packets across the Internet, and then recombining them on the other end: The Internet Protocol (IP), which routes the data, and the Transmission Control Protocol (TCP), which breaks the data into packets and recombines them on the computer that receives the information.