TCP/IP is open standard protocal and it is very fast 
communication protocal.

By using TCP/IP cost is less, very easy to handle, bandwidth
is high etc..

high bandwith with good security

TCP/IP waiting for acknoledgement and it fast and 
realibality.

b'coz it supports both wired & wireless(communication)

OSI
Standard legislated by official recognized body. (ISO)
The OSI reference model was devised before the protocols 
were invented. This ordering means that the model was not 
biased toward one particular set of protocols, which made 
it quite general. The down side of this ordering is that 
the designers did not have much experience with the subject 
and did not have a good idea of which functionality to put 
in which layer.
Being general,the protocols in the OSI model are better 
hidden than in the TCP/IP model and can be replaced 
relatively easily as the technology changes. 
Not so widespread as compared with TCP/IP. (complex , 
costly)
More commonly used as teaching aids.

TCP/IP
Standards adopted due to widespread use. (Internet)
The protocols came first, and the model was really just a 
description of the existing protocols. There was no problem 
with the protocols fitting the model, but it is hardly 
possible to be use to describe other models.
“Get the job done" orientation. 
	Over the years it has handled most challenges by 
growing to meet the needs.
More popular standard for internetworking for several 
reasons :
relatively simple and robust compared to alternatives such 
as OSI 
available on virtually every hardware and operating system 
platform (often free)
the protocol suite on which the Internet depends.

We all know that OSI has 7 layers and TCP/IP suite has 5 
layers. why? In TCP, we can achieve the functions of 
Session and Presentation layers in Application layer 
itself.This makes the TCP/IP protocol suite as a 5 layered. 
The functions of Session and Presentation layer are 
achieved in the Application layer with the help of 
libraries.

tcp/ip is conncetion oriented, secure , reliable and non 
proprietary routable network protocol suite that enables 
computers to communicate over all types of networks. it is 
the native protocol of the internet and is required for 
internet connectivity. and it is of 4 layers instead of 7 
of osi model.
the layers are application, transport,internet and network.
Application-TFTP protocol.
Transport-TCP, UDP
Internet-IP,ARP,ICMP,IGMP
Network-Network Interface Card

bcoz TCP\IP is a very relible and secure model and it is 
also send acknowlegment and high bandwirth