Struct sockaddr{
    unsigned short sa_family;
    char sa_data[14];
}

Struct sockaddr_in{
    short sin_family;
    unsigned short sin_port;//Port Number
    struct in_addr sin_addr;//IP address
    char sin_zero[8];
}

Struct in_addr{
    unsigned long s_addr;//4 byte
}
htons() host to network short
htonl() host to network long
inet_aton() ---> ascitobinary
inet_ntoa() ---> network to ascii