What is an IP address?

The IP address refers to the Internet Protocol Address, and the IP Address is an abbreviation. An IP address is a unified address format provided by the IP protocol. It assigns a logical address to each network and each host on the Internet to shield the difference in physical addresses.

The IP address is used to give a number to a computer (or smartphone) on the Internet. It is common for everyone to have an IP address on each networked PC in order to communicate properly. We can compare "personal computer" to "one phone", then "IP address" is equivalent to "phone number", and the router on the Internet is equivalent to the "programmed switch" of the telecommunications bureau.

The concept of IP addresses: IP addresses are the basis of our TCP/IP communication (Internet Protocol), and each computer connected to the network must have an IP address. The IPv4 IP address we are currently using is 32-bit and is usually split into 4 "8-bit binary numbers" (that is, 4 bytes). The IP address is usually expressed in the form of (a.b.c.d) in "dot-decimal", where a, b, c, and d are all decimal integers between 0 and 255. Example: The decimal point IP address ( is actually a 32-bit binary number (01100100.00000100.00000101.00000110).

IP address format: IP address = network address + host address or IP address = host address + subnet address + host address. A simple IP address actually contains two important pieces of information: the network address and the host address.

Common IP addresses are divided into two categories: IPv4 and IPv6. IPV4 uses a 32-bit address length, which has 4 segments, each segment does not exceed 255, and IPv6 uses a 128-bit address length.

The IP addresses are classified into five types according to the network ID: A/B/C/D/E.

1. Class A: This class is used for very large networks. The IP address from 1 to 126 in the first octet belongs to this group;
2. Class B: This class is used for medium-sized networks. The IP address from 128 to 191 in the first octet belongs to this group;
3. Class C: This class is used for small and medium-sized networks. The IP address from 192 to 223 in the first octet belongs to this group;
4. Class D: This class is used for multicasting. The first to third digits are 1 and the fourth digit is 0.
5. Class E: This class is for experimental purposes only. It is very similar to Class D. The first to third bits have a value of 1. The only difference is that its fourth-bit value is also 1.