TCP/IP Model

TCP/IP

Short for Transmission Control Protocol/Internet Protocol, TCP/IP also commonly abbreviated as TCP was developed in 1978 and driven by Bob Kahn and Vint Cerf. Today, TCP/IP is a language governing communications among all computers on the Internet.

TCP/IP is two separate protocols, TCP and IP, that are used together. The Internet Protocol standard dictates how packets of information are sent out over networks. IP has a packet-addressing method that lets any computer on the Internet forward a packet to another computer that is a step (or more) closer to the packet's recipient. The Transmission Control Protocol ensures the reliability of data transmission across Internet connected networks. TCP checks packets for errors and submits requests for re-transmissions if errors are found.
Three of the most common TCP/IP protocols used are:

• HTTP - Used between a web client and a web server, for non-secure data transmissions. A web client (i.e. Internet browser on a computer) sends a request to a web server to view a web page. The web server receives that request and sends the web page information back to the web client.
• HTTPS - Used between a web client and a web server, for secure data transmissions. Often used for sending credit card transaction data or other private data from a web client (i.e. Internet browser on a computer) to a web server.
• FTP - Used between two or more computers. One computer sends data to or receives data from another computer directly.

References:
http://www.computerhope.com/jargon/t/tcpip.htm
http://learncomputernetwork.blogspot.co.za/2010/02/communication-process-for-tcpip-model.html