How the Internet Works.
Every computer and device that operates within the Internet has a unique identifier known as an Internet protocol (IP) number, or address.
Specific Internet protocols (discussed earlier in this chapter) allow each computer or device on the Internet to use these IP addresses to locate other computers or devices.
The IP address is a four—part number, with each part separated by a period.
All Web sites have an IP address; however, most are also associated with a character-based address, which is easier for people to remember.
The process of associating the numerical IP address with the character-based name is accomplished by a Domain Name System (DNS) server, which is maintained by an ISP.
IP addresses may be static or dynamic.