TCP stands for Transmission Control Protocol and is used to establish a reliable two-way connection over which files and email can be sent and remote login sessions can be conducted. IP stands for "Internet Protocol" remote login sessions can be conducted. IP stands for Internet Protocol and is the main way that packets cross the many individual networks through gateways in order to get to their destinations. Here are a few of the other protocols in the suite:

UDP      User Datagram Protocol, used for sometimes unreliable short messages
SMTP     Simple Mail Transport Protocol, used for email over the Internet
HTTP     Hypertext Transport Protocol, used to transmit web pages and HTML
         documents
FTP      File Transport Protocol, used to reliably send files
Telnet   Remote login and terminal emulation, used to turn a terminal hooked
         to a computer into a terminal of a remote computer
SNMP     Simple Network Management Protocol, used to control gateways and
         hosts and keep statistics on usage and problems
ICMP     Internet Control Message Protocol, used by gateways to tell about
         conditions on the networks and to share routing information