Source : Free On-Line Dictionary of Computing

Internet address
     
         (IP address, {TCP/IP} address) The 32-bit host
        address defined by the {Internet Protocol} in {STD} 5, {RFC}
        791.  It is usually represented in dotted decimal notation.
     
        A hosts's Internet address is sometimes related to its
        {Ethernet address}.  The Internet address is usually expressed
        in {dot notation}, e.g. 128.121.4.5.  The address can be split
        into a {network number} (or network address) and a {host
        number} unique to each host on the network and sometimes also
        a {subnet address}.  The way the address is split depends on
        its "class", A, B or C as determined by the high address bits:
     
        Class A - high bit 0, 7-bit network number, 24-bit host
        number.  n1.a.a.a 0 <= n1 <= 127
     
        Class B - high 2 bits 10, 14-bit network number, 16-bit host
        number.  n1.n2.a.a 128 <= n1 <= 191
     
        Class C - high 3 bits 110, 21-bit network number, 8-bit host
        number.  n1.n2.n3.a 192 <= n1 <= 223
     
        The Internet address must be translated into an {Ethernet
        address} by either {ARP} or {constant mapping}.
     
        The term is sometimes used incorrectly to refer to a host's
        {fully qualified domain name}.
     
        [{Jargon File}]
     
        (1994-12-06)

internet address
     
         (Note lower case "i").  An {IP} address that
        uniquely identifies a node on an {internet}.
     
        [{Jargon File}]
     
        (1995-04-12)