Because an important role on the Windows operating system and also because the TCP / IP is the protocol of choice (default) from Windows. TCP protocol is at the Transport layer of the OSI model (Open Systems Interconnection), while the IP is at the Network layer of the OSI mode.
IP Address : IP address is the address given on computer networks and network equipment that uses TCP / IP. IP addresses consist of 32-bit binary numbers which can be written as four decimal numbers separated by dots such as 192.168.0.1.
IP addresses consist of two parts, namely the network ID and host ID, which determines the network ID address of the computer network, while the host ID determines the address of the host (computers, routers, switches). Therefore, the IP address provides the full address of a host and network address where the host is located.