title: Are we using TCP/IP or OSI in internet?
body: <p>sorry for that question, but i've searched about that topic, and it's not really clear, they say that internet uses tcp/ip but sometimes they say that osi also is used! for example, UDP application, they dont use tcp/ip since it's not a tcp?!</p>
  
  <p>please, can someone make it clear? mean; where is "exactly" OSI is used, and where is "exactly" TCP/IP is used!</p>