title: Difference between TCP and UDP?
body: <p>What is the difference between TCP and UDP? </p>
  
  <p>I know that TCP is used in the case of non-time critical applications, and UDP is used for games or applications that require fast transmission of data. I know that TCP is used for HTTP, HTTPs, FTP, SMTP, and Telnet. I know that UDP is used for DNS and DHCP.</p>
  
  <p>But why? What characteristics of TCP and UDP make it useful for their respective use cases? </p>