Definition of an IP Address A numeric code that identifies a particular computer on the Internet . Just as a street address identifies the location of your home or office , every computer or network on the Internet has a unique address, too. You register your address with InterNIC as both a name , which is referred to as the domain name , and a number ( 198.137.240.100 ) , which is generally referred to as the IP address or IP number. Most likely, the InterNIC will assign you a Class C address, which consists of 255 unique IP numbers for you to assign to your employees. If you need more than 255 IP address, you can apply for a Clas