NetBIOS is an acronym for Network Basic Input/Output System. The NetBIOS API allows applications on separate computers to communicate over a local area network. In modern networks, it normally runs over TCP/IP (NBT), giving each computer in the network both a NetBIOS name and an IP address corresponding to a (possibly different) host name. Older operating systems ran NetBIOS over IPX/SPX or IEEE 802.2 (NBF). NetBIOS provides services related to the session layer of the OSI model.